Programs & Examples On #Httpwebresponse

Provides an HTTP-specific implementation of the WebResponse class

How to get error information when HttpWebRequest.GetResponse() fails

Is this possible using HttpWebRequest and HttpWebResponse?

You could have your web server simply catch and write the exception text into the body of the response, then set status code to 500. Now the client would throw an exception when it encounters a 500 error but you could read the response stream and fetch the message of the exception.

So you could catch a WebException which is what will be thrown if a non 200 status code is returned from the server and read its body:

catch (WebException ex)
{
    using (var stream = ex.Response.GetResponseStream())
    using (var reader = new StreamReader(stream))
    {
        Console.WriteLine(reader.ReadToEnd());
    }
}
catch (Exception ex)
{
    // Something more serious happened
    // like for example you don't have network access
    // we cannot talk about a server exception here as
    // the server probably was never reached
}

How to convert WebResponse.GetResponseStream return into a string?

You can create a StreamReader around the stream, then call StreamReader.ReadToEnd().

StreamReader responseReader = new StreamReader(request.GetResponse().GetResponseStream());
var responseData = responseReader.ReadToEnd();

reading HttpwebResponse json response, C#

If you're getting source in Content Use the following method

try
{
    var response = restClient.Execute<List<EmpModel>>(restRequest);

    var jsonContent = response.Content;

    var data = JsonConvert.DeserializeObject<List<EmpModel>>(jsonContent);

    foreach (EmpModel item in data)
    {
        listPassingData?.Add(item);
    }
}
catch (Exception ex)
{
    Console.WriteLine($"Data get mathod problem {ex} ");
}

Uses of content-disposition in an HTTP response header

Refer to RFC 6266 (Use of the Content-Disposition Header Field in the Hypertext Transfer Protocol (HTTP)) http://tools.ietf.org/html/rfc6266

Error: Address already in use while binding socket with address but the port number is shown free by `netstat`

I've run into that same issue as well. It's because you're closing your connection to the socket, but not the socket itself. The socket can enter a TIME_WAIT state (to ensure all data has been transmitted, TCP guarantees delivery if possible) and take up to 4 minutes to release.

or, for a REALLY detailed/technical explanation, check this link

It's certainly annoying, but it's not a bug. See the comment from @Vereb on this answer below on the use of SO_REUSEADDR.

Get Context in a Service

just in case someone is getting NullPointerException, you need to get the context inside onCreate().

Service is a Context, so do this:

@Override
public void onCreate() {
    super.onCreate();
    context = this;
}

Python - IOError: [Errno 13] Permission denied:

I had a same problem. In my case, the user did not have write permission to the destination directory. Following command helped in my case :

chmod 777 University

PHP date() with timezone?

Not mentioned above. You could also crate a DateTime object by providing a timestamp as string in the constructor with a leading @ sign.

$dt = new DateTime('@123456789');
$dt->setTimezone(new DateTimeZone('America/New_York'));
echo $dt->format('F j, Y - G:i');

See the documentation about compound formats: https://www.php.net/manual/en/datetime.formats.compound.php

PHP Redirect to another page after form submit

You can include your header function wherever you like, as long as NO html and/or text has been printed to standard out.

For more information and usage: http://php.net/manual/en/function.header.php


I see in your code that you echo() out some text in case of error or success. Don't do that: you can't. You can only redirect OR show the text. If you show the text you'll then fail to redirect.

Changing date format in R

This is really easy using package lubridate. All you have to do is tell R what format your date is already in. It then converts it into the standard format

nzd$date <- dmy(nzd$date)

that's it.

Why do you have to link the math library in C?

The functions in stdlib.h and stdio.h have implementations in libc.so (or libc.a for static linking), which is linked into your executable by default (as if -lc were specified). GCC can be instructed to avoid this automatic link with the -nostdlib or -nodefaultlibs options.

The math functions in math.h have implementations in libm.so (or libm.a for static linking), and libm is not linked in by default. There are historical reasons for this libm/libc split, none of them very convincing.

Interestingly, the C++ runtime libstdc++ requires libm, so if you compile a C++ program with GCC (g++), you will automatically get libm linked in.

How to send a "multipart/form-data" with requests in python?

To clarify examples given above,

"You need to use the files parameter to send a multipart form POST request even when you do not need to upload any files."

files={}

won't work, unfortunately.

You will need to put some dummy values in, e.g.

files={"foo": "bar"}

I came up against this when trying to upload files to Bitbucket's REST API and had to write this abomination to avoid the dreaded "Unsupported Media Type" error:

url = "https://my-bitbucket.com/rest/api/latest/projects/FOO/repos/bar/browse/foobar.txt"
payload = {'branch': 'master', 
           'content': 'text that will appear in my file',
           'message': 'uploading directly from python'}
files = {"foo": "bar"}
response = requests.put(url, data=payload, files=files)

:O=

Send an Array with an HTTP Get

I know this post is really old, but I have to reply because although BalusC's answer is marked as correct, it's not completely correct.

You have to write the query adding "[]" to foo like this:

foo[]=val1&foo[]=val2&foo[]=val3

tkinter: Open a new window with a button prompt

Here's the nearly shortest possible solution to your question. The solution works in python 3.x. For python 2.x change the import to Tkinter rather than tkinter (the difference being the capitalization):

import tkinter as tk
#import Tkinter as tk  # for python 2
    
def create_window():
    window = tk.Toplevel(root)

root = tk.Tk()
b = tk.Button(root, text="Create new window", command=create_window)
b.pack()

root.mainloop()

This is definitely not what I recommend as an example of good coding style, but it illustrates the basic concepts: a button with a command, and a function that creates a window.

Dataframe to Excel sheet

From your above needs, you will need to use both Python (to export pandas data frame) and VBA (to delete existing worksheet content and copy/paste external data).

With Python: use the to_csv or to_excel methods. I recommend the to_csv method which performs better with larger datasets.

# DF TO EXCEL
from pandas import ExcelWriter

writer = ExcelWriter('PythonExport.xlsx')
yourdf.to_excel(writer,'Sheet5')
writer.save()

# DF TO CSV
yourdf.to_csv('PythonExport.csv', sep=',')

With VBA: copy and paste source to destination ranges.

Fortunately, in VBA you can call Python scripts using Shell (assuming your OS is Windows).

Sub DataFrameImport()
  'RUN PYTHON TO EXPORT DATA FRAME
  Shell "C:\pathTo\python.exe fullpathOfPythonScript.py", vbNormalFocus

  'CLEAR EXISTING CONTENT
  ThisWorkbook.Worksheets(5).Cells.Clear

  'COPY AND PASTE TO WORKBOOK
  Workbooks("PythonExport").Worksheets(1).Cells.Copy
  ThisWorkbook.Worksheets(5).Range("A1").Select
  ThisWorkbook.Worksheets(5).Paste
End Sub

Alternatively, you can do vice versa: run a macro (ClearExistingContent) with Python. Be sure your Excel file is a macro-enabled (.xlsm) one with a saved macro to delete Sheet 5 content only. Note: macros cannot be saved with csv files.

import os
import win32com.client
from pandas import ExcelWriter

if os.path.exists("C:\Full Location\To\excelsheet.xlsm"):
  xlApp=win32com.client.Dispatch("Excel.Application")
  wb = xlApp.Workbooks.Open(Filename="C:\Full Location\To\excelsheet.xlsm")

  # MACRO TO CLEAR SHEET 5 CONTENT
  xlApp.Run("ClearExistingContent")
  wb.Save() 
  xlApp.Quit()
  del xl

  # WRITE IN DATA FRAME TO SHEET 5
  writer = ExcelWriter('C:\Full Location\To\excelsheet.xlsm')
  yourdf.to_excel(writer,'Sheet5')
  writer.save() 

Pressing Ctrl + A in Selenium WebDriver

I found that in Ruby, you can pass two arguments to send_keys

Like this:

element.send_keys(:control, 'A')

Why am I getting "Unable to find manifest signing certificate in the certificate store" in my Excel Addin?

Make sure you commit .pfx files to repository.

I just found *.pfx in my default .gitignore. Comment it (by #) and commit changes. Then pull repository and rebuild.

HTML table sort

Here is another library.

Changes required are -

  1. Add sorttable js

  2. Add class name sortable to table.

Click the table headers to sort the table accordingly:

_x000D_
_x000D_
<script src="https://www.kryogenix.org/code/browser/sorttable/sorttable.js"></script>

<table class="sortable">
  <tr>
    <th>Name</th>
    <th>Address</th>
    <th>Sales Person</th>
  </tr>

  <tr class="item">
    <td>user:0001</td>
    <td>UK</td>
    <td>Melissa</td>
  </tr>
  <tr class="item">
    <td>user:0002</td>
    <td>France</td>
    <td>Justin</td>
  </tr>
  <tr class="item">
    <td>user:0003</td>
    <td>San Francisco</td>
    <td>Judy</td>
  </tr>
  <tr class="item">
    <td>user:0004</td>
    <td>Canada</td>
    <td>Skipper</td>
  </tr>
  <tr class="item">
    <td>user:0005</td>
    <td>Christchurch</td>
    <td>Alex</td>
  </tr>

</table>
_x000D_
_x000D_
_x000D_

Could not find method android() for arguments

This error appear because the compiler could not found "my-upload-key.keystore" file in your project

After you have generated the file you need to paste it into project's andorid/app folder

this worked for me!

What is a vertical tab?

I have found that the VT char is used in pptx text boxes at the end of each line shown in the box in oder to adjust the text to the size of the box. It seems to be automatically generated by powerpoint (not introduced by the user) in order to move the text to the next line and fix the complete text block to the text box. In the example below, in the position of §:

"This is a text §
inside a text box"

Accessing @attribute from SimpleXML

You can get the attributes of an XML element by calling the attributes() function on an XML node. You can then var_dump the return value of the function.

More info at php.net http://php.net/simplexmlelement.attributes

Example code from that page:

$xml = simplexml_load_string($string);
foreach($xml->foo[0]->attributes() as $a => $b) {
    echo $a,'="',$b,"\"\n";
}

Ordering by the order of values in a SQL IN() clause

I just tried to do this is MS SQL Server where we do not have FIELD():

SELECT table1.id
... 
INNER JOIN
    (VALUES (10,1),(3,2),(4,3),(5,4),(7,5),(8,6),(9,7),(2,8),(6,9),(5,10)
    ) AS X(id,sortorder)
        ON X.id = table1.id
    ORDER BY X.sortorder

Note that I am allowing duplication too.

Removing MySQL 5.7 Completely

You need to remove the /var/lib/mysql folder. Also, purge when you remove the packages (I'm told this helps).

sudo apt-get remove --purge mysql-server mysql-client mysql-common

sudo rm -rf /var/lib/mysql

I was encountering similar issues. The second line got rid of my issues and allowed me to set up MySql from scratch. Hopefully it helps you too!

How to dynamically add rows to a table in ASP.NET?

You need to get familiar with the idea of "Server side" vs. "Client side" code. It's been a long time since I had to start, but you may want to start with some of the video tutorials at http://www.asp.net.

Two things to note: if you're using VS2010 you actually have two different frameworks to chose from for ASP.NET: WebForms and ASP.NET MVC2. WebForms is the old legacy way, MVC2 is being positioned by MS as an alternative not a replacement for WebForms, but we'll see how the community handles it over the next couple of years. Anyway, be sure to pay attention to which one a given tutorial is talking about.

git rebase fatal: Needed a single revision

git submodule deinit --all -f worked for me.

What is the best/simplest way to read in an XML file in Java application?

Depending on your application and the scope of the cfg file, a properties file might be the easiest. Sure it isn't as elegant as xml but it certainly easier.

String literals and escape characters in postgresql

Partially. The text is inserted, but the warning is still generated.

I found a discussion that indicated the text needed to be preceded with 'E', as such:

insert into EscapeTest (text) values (E'This is the first part \n And this is the second');

This suppressed the warning, but the text was still not being returned correctly. When I added the additional slash as Michael suggested, it worked.

As such:

insert into EscapeTest (text) values (E'This is the first part \\n And this is the second');

Why is there still a row limit in Microsoft Excel?

Probably because of optimizations. Excel 2007 can have a maximum of 16 384 columns and 1 048 576 rows. Strange numbers?

14 bits = 16 384, 20 bits = 1 048 576

14 + 20 = 34 bits = more than one 32 bit register can hold.

But they also need to store the format of the cell (text, number etc) and formatting (colors, borders etc). Assuming they use two 32-bit words (64 bit) they use 34 bits for the cell number and have 30 bits for other things.

Why is that important? In memory they don't need to allocate all the memory needed for the whole spreadsheet but only the memory necessary for your data, and every data is tagged with in what cell it is supposed to be in.

Update 2016:

Found a link to Microsoft's specification for Excel 2013 & 2016

  • Open workbooks: Limited by available memory and system resources
  • Worksheet size: 1,048,576 rows (20 bits) by 16,384 columns (14 bits)
  • Column width: 255 characters (8 bits)
  • Row height: 409 points
  • Page breaks: 1,026 horizontal and vertical (unexpected number, probably wrong, 10 bits is 1024)
  • Total number of characters that a cell can contain: 32,767 characters (signed 16 bits)
  • Characters in a header or footer: 255 (8 bits)
  • Sheets in a workbook: Limited by available memory (default is 1 sheet)
  • Colors in a workbook: 16 million colors (32 bit with full access to 24 bit color spectrum)
  • Named views in a workbook: Limited by available memory
  • Unique cell formats/cell styles: 64,000 (16 bits = 65536)
  • Fill styles: 256 (8 bits)
  • Line weight and styles: 256 (8 bits)
  • Unique font types: 1,024 (10 bits) global fonts available for use; 512 per workbook
  • Number formats in a workbook: Between 200 and 250, depending on the language version of Excel that you have installed
  • Names in a workbook: Limited by available memory
  • Windows in a workbook: Limited by available memory
  • Hyperlinks in a worksheet: 66,530 hyperlinks (unexpected number, probably wrong. 16 bits = 65536)
  • Panes in a window: 4
  • Linked sheets: Limited by available memory
  • Scenarios: Limited by available memory; a summary report shows only the first 251 scenarios
  • Changing cells in a scenario: 32
  • Adjustable cells in Solver: 200
  • Custom functions: Limited by available memory
  • Zoom range: 10 percent to 400 percent
  • Reports: Limited by available memory
  • Sort references: 64 in a single sort; unlimited when using sequential sorts
  • Undo levels: 100
  • Fields in a data form: 32
  • Workbook parameters: 255 parameters per workbook
  • Items displayed in filter drop-down lists: 10,000

get current date with 'yyyy-MM-dd' format in Angular 4

If you only want to display then you can use date pipe in HTML like this :

Just Date:

your date | date: 'dd MMM yyyy'

Date With Time:

your date | date: 'dd MMM yyyy hh:mm a'

And if you want to take input only date from new Date() then :

You can use angular formatDate() in ts file like this -

currentDate = new Date();

const cValue = formatDate(currentDate, 'yyyy-MM-dd', 'en-US');

How can I replace a regex substring match in Javascript?

I would get the part before and after what you want to replace and put them either side.

Like:

var str   = 'asd-0.testing';
var regex = /(asd-)\d(\.\w+)/;

var matches = str.match(regex);

var result = matches[1] + "1" + matches[2];

// With ES6:
var result = `${matches[1]}1${matches[2]}`;

Does the Java &= operator apply & or &&?

i came across a similar situation using booleans where I wanted to avoid calling b() if a was already false.

This worked for me:

a &= a && b()

Div not expanding even with content inside

div will not expand if it has other floating divs inside, so remove the float from the internal divs and it will expand.

How to UPSERT (MERGE, INSERT ... ON DUPLICATE UPDATE) in PostgreSQL?

9.5 and newer:

PostgreSQL 9.5 and newer support INSERT ... ON CONFLICT (key) DO UPDATE (and ON CONFLICT (key) DO NOTHING), i.e. upsert.

Comparison with ON DUPLICATE KEY UPDATE.

Quick explanation.

For usage see the manual - specifically the conflict_action clause in the syntax diagram, and the explanatory text.

Unlike the solutions for 9.4 and older that are given below, this feature works with multiple conflicting rows and it doesn't require exclusive locking or a retry loop.

The commit adding the feature is here and the discussion around its development is here.


If you're on 9.5 and don't need to be backward-compatible you can stop reading now.


9.4 and older:

PostgreSQL doesn't have any built-in UPSERT (or MERGE) facility, and doing it efficiently in the face of concurrent use is very difficult.

This article discusses the problem in useful detail.

In general you must choose between two options:

  • Individual insert/update operations in a retry loop; or
  • Locking the table and doing batch merge

Individual row retry loop

Using individual row upserts in a retry loop is the reasonable option if you want many connections concurrently trying to perform inserts.

The PostgreSQL documentation contains a useful procedure that'll let you do this in a loop inside the database. It guards against lost updates and insert races, unlike most naive solutions. It will only work in READ COMMITTED mode and is only safe if it's the only thing you do in the transaction, though. The function won't work correctly if triggers or secondary unique keys cause unique violations.

This strategy is very inefficient. Whenever practical you should queue up work and do a bulk upsert as described below instead.

Many attempted solutions to this problem fail to consider rollbacks, so they result in incomplete updates. Two transactions race with each other; one of them successfully INSERTs; the other gets a duplicate key error and does an UPDATE instead. The UPDATE blocks waiting for the INSERT to rollback or commit. When it rolls back, the UPDATE condition re-check matches zero rows, so even though the UPDATE commits it hasn't actually done the upsert you expected. You have to check the result row counts and re-try where necessary.

Some attempted solutions also fail to consider SELECT races. If you try the obvious and simple:

-- THIS IS WRONG. DO NOT COPY IT. It's an EXAMPLE.

BEGIN;

UPDATE testtable
SET somedata = 'blah'
WHERE id = 2;

-- Remember, this is WRONG. Do NOT COPY IT.

INSERT INTO testtable (id, somedata)
SELECT 2, 'blah'
WHERE NOT EXISTS (SELECT 1 FROM testtable WHERE testtable.id = 2);

COMMIT;

then when two run at once there are several failure modes. One is the already discussed issue with an update re-check. Another is where both UPDATE at the same time, matching zero rows and continuing. Then they both do the EXISTS test, which happens before the INSERT. Both get zero rows, so both do the INSERT. One fails with a duplicate key error.

This is why you need a re-try loop. You might think that you can prevent duplicate key errors or lost updates with clever SQL, but you can't. You need to check row counts or handle duplicate key errors (depending on the chosen approach) and re-try.

Please don't roll your own solution for this. Like with message queuing, it's probably wrong.

Bulk upsert with lock

Sometimes you want to do a bulk upsert, where you have a new data set that you want to merge into an older existing data set. This is vastly more efficient than individual row upserts and should be preferred whenever practical.

In this case, you typically follow the following process:

  • CREATE a TEMPORARY table

  • COPY or bulk-insert the new data into the temp table

  • LOCK the target table IN EXCLUSIVE MODE. This permits other transactions to SELECT, but not make any changes to the table.

  • Do an UPDATE ... FROM of existing records using the values in the temp table;

  • Do an INSERT of rows that don't already exist in the target table;

  • COMMIT, releasing the lock.

For example, for the example given in the question, using multi-valued INSERT to populate the temp table:

BEGIN;

CREATE TEMPORARY TABLE newvals(id integer, somedata text);

INSERT INTO newvals(id, somedata) VALUES (2, 'Joe'), (3, 'Alan');

LOCK TABLE testtable IN EXCLUSIVE MODE;

UPDATE testtable
SET somedata = newvals.somedata
FROM newvals
WHERE newvals.id = testtable.id;

INSERT INTO testtable
SELECT newvals.id, newvals.somedata
FROM newvals
LEFT OUTER JOIN testtable ON (testtable.id = newvals.id)
WHERE testtable.id IS NULL;

COMMIT;

Related reading

What about MERGE?

SQL-standard MERGE actually has poorly defined concurrency semantics and is not suitable for upserting without locking a table first.

It's a really useful OLAP statement for data merging, but it's not actually a useful solution for concurrency-safe upsert. There's lots of advice to people using other DBMSes to use MERGE for upserts, but it's actually wrong.

Other DBs:

Excel Date Conversion from yyyymmdd to mm/dd/yyyy

Do you have ROWS of data (horizontal) as you stated or COLUMNS (vertical)?

If it's the latter you can use "Text to columns" functionality to convert a whole column "in situ" - to do that:

Select column > Data > Text to columns > Next > Next > Choose "Date" under "column data format" and "YMD" from dropdown > Finish

....otherwise you can convert with a formula by using

=TEXT(A1,"0000-00-00")+0

and format in required date format

RS256 vs HS256: What's the difference?

There is a difference in performance.

Simply put HS256 is about 1 order of magnitude faster than RS256 for verification but about 2 orders of magnitude faster than RS256 for issuing (signing).

 640,251  91,464.3 ops/s
  86,123  12,303.3 ops/s (RS256 verify)
   7,046   1,006.5 ops/s (RS256 sign)

Don't get hung up on the actual numbers, just think of them with respect of each other.

[Program.cs]

class Program
{
    static void Main(string[] args)
    {
        foreach (var duration in new[] { 1, 3, 5, 7 })
        {
            var t = TimeSpan.FromSeconds(duration);

            byte[] publicKey, privateKey;

            using (var rsa = new RSACryptoServiceProvider())
            {
                publicKey = rsa.ExportCspBlob(false);
                privateKey = rsa.ExportCspBlob(true);
            }

            byte[] key = new byte[64];

            using (var rng = new RNGCryptoServiceProvider())
            {
                rng.GetBytes(key);
            }

            var s1 = new Stopwatch();
            var n1 = 0;

            using (var hs256 = new HMACSHA256(key))
            {
                while (s1.Elapsed < t)
                {
                    s1.Start();
                    var hash = hs256.ComputeHash(privateKey);
                    s1.Stop();
                    n1++;
                }
            }

            byte[] sign;

            using (var rsa = new RSACryptoServiceProvider())
            {
                rsa.ImportCspBlob(privateKey);

                sign = rsa.SignData(privateKey, "SHA256");
            }

            var s2 = new Stopwatch();
            var n2 = 0;

            using (var rsa = new RSACryptoServiceProvider())
            {
                rsa.ImportCspBlob(publicKey);

                while (s2.Elapsed < t)
                {
                    s2.Start();
                    var success = rsa.VerifyData(privateKey, "SHA256", sign);
                    s2.Stop();
                    n2++;
                }
            }

            var s3 = new Stopwatch();
            var n3 = 0;

            using (var rsa = new RSACryptoServiceProvider())
            {
                rsa.ImportCspBlob(privateKey);

                while (s3.Elapsed < t)
                {
                    s3.Start();
                    rsa.SignData(privateKey, "SHA256");
                    s3.Stop();
                    n3++;
                }
            }

            Console.WriteLine($"{s1.Elapsed.TotalSeconds:0} {n1,7:N0} {n1 / s1.Elapsed.TotalSeconds,9:N1} ops/s");
            Console.WriteLine($"{s2.Elapsed.TotalSeconds:0} {n2,7:N0} {n2 / s2.Elapsed.TotalSeconds,9:N1} ops/s");
            Console.WriteLine($"{s3.Elapsed.TotalSeconds:0} {n3,7:N0} {n3 / s3.Elapsed.TotalSeconds,9:N1} ops/s");

            Console.WriteLine($"RS256 is {(n1 / s1.Elapsed.TotalSeconds) / (n2 / s2.Elapsed.TotalSeconds),9:N1}x slower (verify)");
            Console.WriteLine($"RS256 is {(n1 / s1.Elapsed.TotalSeconds) / (n3 / s3.Elapsed.TotalSeconds),9:N1}x slower (issue)");

            // RS256 is about 7.5x slower, but it can still do over 10K ops per sec.
        }
    }
}

How to change the default charset of a MySQL table?

You can change the default with an alter table set default charset but that won't change the charset of the existing columns. To change that you need to use a alter table modify column.

Changing the charset of a column only means that it will be able to store a wider range of characters. Your application talks to the db using the mysql client so you may need to change the client encoding as well.

CSS selector last row from main table

Your tables should have as immediate children just tbody and thead elements, with the rows within*. So, amend the HTML to be:

<table border="1" width="100%" id="test">
  <tbody>
    <tr>
     <td>
      <table border="1" width="100%">
        <tbody>
          <tr>
            <td>table 2</td>
          </tr>
        </tbody>
      </table>
     </td>
    </tr> 
    <tr><td>table 1</td></tr>
    <tr><td>table 1</td></tr>
    <tr><td>table 1</td></tr>
  </tbody>
</table>

Then amend your selector slightly to this:

#test > tbody > tr:last-child { background:#ff0000; }

See it in action here. That makes use of the child selector, which:

...separates two selectors and matches only those elements matched by the second selector that are direct children of elements matched by the first.

So, you are targeting only direct children of tbody elements that are themselves direct children of your #test table.

Alternative solution

The above is the neatest solution, as you don't need to over-ride any styles. The alternative would be to stick with your current set-up, and over-ride the background style for the inner table, like this:

#test tr:last-child { background:#ff0000; }
#test table tr:last-child { background:transparent; }

* It's not mandatory but most (all?) browsers will add these in, so it's best to make it explicit. As @BoltClock states in the comments:

...it's now set in stone in HTML5, so for a browser to be compliant it basically must behave this way.

Unable to run Java code with Intellij IDEA

If you can't run your correct program and you try all other answers.Click on Edit Configuration and just do following steps-:

  1. Click on add icon and select Application from the list.
  2. In configuration name your Main class: as your main class name.
  3. Set working directory to your project directory.
  4. Others: leave them default and click on apply. Now you can run your program.enter image description here

Dynamically add item to jQuery Select2 control that uses AJAX

This provided a simple solution: Set data in Select2 after insert with AJAX

$("#select2").select2('data', {id: newID, text: newText});      

Set Locale programmatically

Hope this help(in onResume):

Locale locale = new Locale("ru");
Locale.setDefault(locale);
Configuration config = getBaseContext().getResources().getConfiguration();
config.locale = locale;
getBaseContext().getResources().updateConfiguration(config,
      getBaseContext().getResources().getDisplayMetrics());

How to clear all inputs, selects and also hidden fields in a form using jQuery?

for empty all input tags such as input,select,textatea etc. run this code

$('#message').val('').change();

CheckBox in RecyclerView keeps on checking different items

Adding setItemViewCacheSize(int size) to recyclerview and passing size of list solved my problem.

mycode:

mrecyclerview.setItemViewCacheSize(mOrderList.size());
mBinding.mrecyclerview.setAdapter(mAdapter);

Source: https://stackoverflow.com/a/46951440/10459907

What are all the user accounts for IIS/ASP.NET and how do they differ?

This is a very good question and sadly many developers don't ask enough questions about IIS/ASP.NET security in the context of being a web developer and setting up IIS. So here goes....

To cover the identities listed:

IIS_IUSRS:

This is analogous to the old IIS6 IIS_WPG group. It's a built-in group with it's security configured such that any member of this group can act as an application pool identity.

IUSR:

This account is analogous to the old IUSR_<MACHINE_NAME> local account that was the default anonymous user for IIS5 and IIS6 websites (i.e. the one configured via the Directory Security tab of a site's properties).

For more information about IIS_IUSRS and IUSR see:

Understanding Built-In User and Group Accounts in IIS 7

DefaultAppPool:

If an application pool is configured to run using the Application Pool Identity feature then a "synthesised" account called IIS AppPool\<pool name> will be created on the fly to used as the pool identity. In this case there will be a synthesised account called IIS AppPool\DefaultAppPool created for the life time of the pool. If you delete the pool then this account will no longer exist. When applying permissions to files and folders these must be added using IIS AppPool\<pool name>. You also won't see these pool accounts in your computers User Manager. See the following for more information:

Application Pool Identities

ASP.NET v4.0: -

This will be the Application Pool Identity for the ASP.NET v4.0 Application Pool. See DefaultAppPool above.

NETWORK SERVICE: -

The NETWORK SERVICE account is a built-in identity introduced on Windows 2003. NETWORK SERVICE is a low privileged account under which you can run your application pools and websites. A website running in a Windows 2003 pool can still impersonate the site's anonymous account (IUSR_ or whatever you configured as the anonymous identity).

In ASP.NET prior to Windows 2008 you could have ASP.NET execute requests under the Application Pool account (usually NETWORK SERVICE). Alternatively you could configure ASP.NET to impersonate the site's anonymous account via the <identity impersonate="true" /> setting in web.config file locally (if that setting is locked then it would need to be done by an admin in the machine.config file).

Setting <identity impersonate="true"> is common in shared hosting environments where shared application pools are used (in conjunction with partial trust settings to prevent unwinding of the impersonated account).

In IIS7.x/ASP.NET impersonation control is now configured via the Authentication configuration feature of a site. So you can configure to run as the pool identity, IUSR or a specific custom anonymous account.

LOCAL SERVICE:

The LOCAL SERVICE account is a built-in account used by the service control manager. It has a minimum set of privileges on the local computer. It has a fairly limited scope of use:

LocalService Account

LOCAL SYSTEM:

You didn't ask about this one but I'm adding for completeness. This is a local built-in account. It has fairly extensive privileges and trust. You should never configure a website or application pool to run under this identity.

LocalSystem Account

In Practice:

In practice the preferred approach to securing a website (if the site gets its own application pool - which is the default for a new site in IIS7's MMC) is to run under Application Pool Identity. This means setting the site's Identity in its Application Pool's Advanced Settings to Application Pool Identity:

enter image description here

In the website you should then configure the Authentication feature:

enter image description here

Right click and edit the Anonymous Authentication entry:

enter image description here

Ensure that "Application pool identity" is selected:

enter image description here

When you come to apply file and folder permissions you grant the Application Pool identity whatever rights are required. For example if you are granting the application pool identity for the ASP.NET v4.0 pool permissions then you can either do this via Explorer:

enter image description here

Click the "Check Names" button:

enter image description here

Or you can do this using the ICACLS.EXE utility:

icacls c:\wwwroot\mysite /grant "IIS AppPool\ASP.NET v4.0":(CI)(OI)(M)

...or...if you site's application pool is called BobsCatPicBlogthen:

icacls c:\wwwroot\mysite /grant "IIS AppPool\BobsCatPicBlog":(CI)(OI)(M)

I hope this helps clear things up.

Update:

I just bumped into this excellent answer from 2009 which contains a bunch of useful information, well worth a read:

The difference between the 'Local System' account and the 'Network Service' account?

MavenError: Failed to execute goal on project: Could not resolve dependencies In Maven Multimodule project

In my case I forgot it was packaging conflict jar vs pom. I forgot to write

<packaging>pom</packaging>

In every child pom.xml file

How to get correlation of two vectors in python

The docs indicate that numpy.correlate is not what you are looking for:

numpy.correlate(a, v, mode='valid', old_behavior=False)[source]
  Cross-correlation of two 1-dimensional sequences.
  This function computes the correlation as generally defined in signal processing texts:
     z[k] = sum_n a[n] * conj(v[n+k])
  with a and v sequences being zero-padded where necessary and conj being the conjugate.

Instead, as the other comments suggested, you are looking for a Pearson correlation coefficient. To do this with scipy try:

from scipy.stats.stats import pearsonr   
a = [1,4,6]
b = [1,2,3]   
print pearsonr(a,b)

This gives

(0.99339926779878274, 0.073186395040328034)

You can also use numpy.corrcoef:

import numpy
print numpy.corrcoef(a,b)

This gives:

[[ 1.          0.99339927]
 [ 0.99339927  1.        ]]

How to check if matching text is found in a string in Lua?

There are 2 options to find matching text; string.match or string.find.

Both of these perform a regex search on the string to find matches.


string.find()

string.find(subject string, pattern string, optional start position, optional plain flag)

Returns the startIndex & endIndex of the substring found.

The plain flag allows for the pattern to be ignored and intead be interpreted as a literal. Rather than (tiger) being interpreted as a regex capture group matching for tiger, it instead looks for (tiger) within a string.

Going the other way, if you want to regex match but still want literal special characters (such as .()[]+- etc.), you can escape them with a percentage; %(tiger%).

You will likely use this in combination with string.sub

Example

str = "This is some text containing the word tiger."
if string.find(str, "tiger") then
  print ("The word tiger was found.")
else
  print ("The word tiger was not found.")
end

string.match()

string.match(s, pattern, optional index)

Returns the capture groups found.

Example

str = "This is some text containing the word tiger."
if string.match(str, "tiger") then
  print ("The word tiger was found.")
else
  print ("The word tiger was not found.")
end

Scroll to bottom of div with Vue.js

As I understood, the desired effect you want is to scroll to the end of a list (or scrollable div) when something happens (e.g.: a item is added to the list). If so, you can scroll to the end of a container element (or even the page it self) using only pure Javascript and the VueJS selectors.

var container = this.$el.querySelector("#container");
container.scrollTop = container.scrollHeight;

I've provided a working example in this fiddle: https://jsfiddle.net/my54bhwn

Every time a item is added to the list, the list is scrolled to the end to show the new item.

Hope this help you.

org.json.simple cannot be resolved

The jar file is missing. You can download the jar file and add it as external libraries in your project . You can download this from

http://www.findjar.com/jar/com/googlecode/json-simple/json-simple/1.1/json-simple-1.1.jar.html

pull access denied repository does not exist or may require docker login

If you're downloading from somewhere else than your own registry or docker-hub, you might have to do a separate agreement of terms on their site, like the case with Oracle's docker registry. It allows you to do docker login fine, but pulling the container won't still work until you go to their site and agree on their terms.

Remove a specific string from an array of string

import java.util.*;

class Array {
    public static void main(String args[]) {
        ArrayList al = new ArrayList();
        al.add("google");
        al.add("microsoft");
        al.add("apple");
        System.out.println(al);
        //i only remove the apple//
        al.remove(2);
        System.out.println(al);
    }
}

How do I get the value of text input field using JavaScript?

You can read value by

searchTxt.value

_x000D_
_x000D_
function searchURL() {
   let txt = searchTxt.value;
   console.log(txt);
   // window.location = "http://www.myurl.com/search/" + txt; ...
}

document.querySelector('.search').addEventListener("click", ()=>searchURL());
_x000D_
<input name="searchTxt" type="text" maxlength="512" id="searchTxt" class="searchField"/>

<button class="search">Search</button>
_x000D_
_x000D_
_x000D_

UPDATE

I see many downvotes but any comments - however (for future readers) actually this solution works

What's the difference between .so, .la and .a library files?

.so files are dynamic libraries. The suffix stands for "shared object", because all the applications that are linked with the library use the same file, rather than making a copy in the resulting executable.

.a files are static libraries. The suffix stands for "archive", because they're actually just an archive (made with the ar command -- a predecessor of tar that's now just used for making libraries) of the original .o object files.

.la files are text files used by the GNU "libtools" package to describe the files that make up the corresponding library. You can find more information about them in this question: What are libtool's .la file for?

Static and dynamic libraries each have pros and cons.

Static pro: The user always uses the version of the library that you've tested with your application, so there shouldn't be any surprising compatibility problems.

Static con: If a problem is fixed in a library, you need to redistribute your application to take advantage of it. However, unless it's a library that users are likely to update on their own, you'd might need to do this anyway.

Dynamic pro: Your process's memory footprint is smaller, because the memory used for the library is amortized among all the processes using the library.

Dynamic pro: Libraries can be loaded on demand at run time; this is good for plugins, so you don't have to choose the plugins to be used when compiling and installing the software. New plugins can be added on the fly.

Dynamic con: The library might not exist on the system where someone is trying to install the application, or they might have a version that's not compatible with the application. To mitigate this, the application package might need to include a copy of the library, so it can install it if necessary. This is also often mitigated by package managers, which can download and install any necessary dependencies.

Dynamic con: Link-Time Optimization is generally not possible, so there could possibly be efficiency implications in high-performance applications. See the Wikipedia discussion of WPO and LTO.

Dynamic libraries are especially useful for system libraries, like libc. These libraries often need to include code that's dependent on the specific OS and version, because kernel interfaces have changed. If you link a program with a static system library, it will only run on the version of the OS that this library version was written for. But if you use a dynamic library, it will automatically pick up the library that's installed on the system you run on.

How to install cron

Do you have a Windows machine or a Linux machine?

Under Windows cron is called 'Scheduled Tasks'. It's located in the Control Panel. You can set several scripts to run at specified times in the control panel. Use the wizard to define the scheduled times. Be sure that PHP is callable in your PATH.

Under Linux you can create a crontab for your current user by typing:

crontab -e [username]

If this command fails, it's likely that cron is not installed. If you use a Debian based system (Debian, Ubuntu), try the following commands first:

sudo apt-get update
sudo apt-get install cron

If the command runs properly, a text editor will appear. Now you can add command lines to the crontab file. To run something every five minutes:

*/5 * * * *  /home/user/test.pl

The syntax is basically this:

.---------------- minute (0 - 59) 
|  .------------- hour (0 - 23)
|  |  .---------- day of month (1 - 31)
|  |  |  .------- month (1 - 12) OR jan,feb,mar,apr ... 
|  |  |  |  .---- day of week (0 - 6) (Sunday=0 or 7)  OR sun,mon,tue,wed,thu,fri,sat 
|  |  |  |  |
*  *  *  *  *  command to be executed

Read more about it on the following pages: Wikipedia: crontab

Hash table in JavaScript

You could use my JavaScript hash table implementation, jshashtable. It allows any object to be used as a key, not just strings.

Returning JSON object from an ASP.NET page

With ASP.NET Web Pages you can do this on a single page as a basic GET example (the simplest possible thing that can work.

var json = Json.Encode(new {
    orientation = Cache["orientation"],
    alerted = Cache["alerted"] as bool?,
    since = Cache["since"] as DateTime?
});
Response.Write(json);

Is a DIV inside a TD a bad idea?

It breaks semantics, that's all. It works fine, but there may be screen readers or something down the road that won't enjoy processing your HTML if you "break semantics".

Convert date to datetime in Python

Today being 2016, I think the cleanest solution is provided by pandas Timestamp:

from datetime import date
import pandas as pd
d = date.today()
pd.Timestamp(d)

Timestamp is the pandas equivalent of datetime and is interchangable with it in most cases. Check:

from datetime import datetime
isinstance(pd.Timestamp(d), datetime)

But in case you really want a vanilla datetime, you can still do:

pd.Timestamp(d).to_datetime()

Timestamps are a lot more powerful than datetimes, amongst others when dealing with timezones. Actually, Timestamps are so powerful that it's a pity they are so poorly documented...

Using multiple case statements in select query

There are two ways to write case statements, you seem to be using a combination of the two

case a.updatedDate
    when 1760 then 'Entered on' + a.updatedDate
    when 1710 then 'Viewed on' + a.updatedDate
    else 'Last Updated on' + a.updateDate
end

or

case 
    when a.updatedDate = 1760 then 'Entered on' + a.updatedDate
    when a.updatedDate = 1710 then 'Viewed on' + a.updatedDate
    else 'Last Updated on' + a.updateDate
end

are equivalent. They may not work because you may need to convert date types to varchars to append them to other varchars.

How to add text to a WPF Label in code?

You can use the Content property on pretty much all visual WPF controls to access the stuff inside them. There's a heirarchy of classes that the controls belong to, and any descendants of ContentControl will work in this way.

Quick way to create a list of values in C#?

IList<string> list = new List<string> {"test1", "test2", "test3"}

Comparison of C++ unit test frameworks

CppUTest - very nice, light weight framework with mock libraries. Worthwhile taking a closer look.

Restful API service

Also when I hit the post(Config.getURL("login"), values) the app seems to pause for a while (seems weird - thought the idea behind a service was that it runs on a different thread!)

In this case its better to use asynctask, which runs on a different thread and return result back to the ui thread on completion.

Set the table column width constant regardless of the amount of text in its cells?

It also helps, to put in the last "filler cell", with width:auto. This will occupy remaining space, and will leave all other dimensions as specified.

Selecting multiple columns in a Pandas dataframe

To select multiple columns, extract and view them thereafter: df is previously named data frame, than create new data frame df1, and select the columns A to D which you want to extract and view.

df1 = pd.DataFrame(data_frame, columns=['Column A', 'Column B', 'Column C', 'Column D'])
df1

All required columns will show up!

Show hide divs on click in HTML and CSS without jQuery

Using display:none is not SEO-friendly. The following way allows the hidden content to be searchable. Adding the transition-delay ensures any links included in the hidden content is clickable.

.collapse > p{
cursor: pointer;
display: block;
}

.collapse:focus{
outline: none;
}

.collapse > div {
height: 0;
width: 0;
overflow: hidden;
transition-delay: 0.3s;
}

.collapse:focus div{
display: block; 
height: 100%;
width: 100%;
overflow: auto;
}

<div class="collapse" tabindex="1">
<p>Question 1</p>
<div>
  <p>Visit <a href="https://stackoverflow.com/">Stack Overflow</a></p>
</div>
</div>
<div class="collapse" tabindex="2">
<p>Question 2</p>
<div>
  <p>Visit <a href="https://stackoverflow.com/">Stack Overflow</a></p>
</div>
</div> 

Equals(=) vs. LIKE

The equals (=) operator is a "comparison operator compares two values for equality." In other words, in an SQL statement, it won't return true unless both sides of the equation are equal. For example:

SELECT * FROM Store WHERE Quantity = 200;

The LIKE operator "implements a pattern match comparison" that attempts to match "a string value against a pattern string containing wild-card characters." For example:

SELECT * FROM Employees WHERE Name LIKE 'Chris%';

LIKE is generally used only with strings and equals (I believe) is faster. The equals operator treats wild-card characters as literal characters. The difference in results returned are as follows:

SELECT * FROM Employees WHERE Name = 'Chris';

And

SELECT * FROM Employees WHERE Name LIKE 'Chris';

Would return the same result, though using LIKE would generally take longer as its a pattern match. However,

SELECT * FROM Employees WHERE Name = 'Chris%';

And

SELECT * FROM Employees WHERE Name LIKE 'Chris%';

Would return different results, where using "=" results in only results with "Chris%" being returned and the LIKE operator will return anything starting with "Chris".

Hope that helps. Some good info can be found here.

Best way to use multiple SSH private keys on one client

As mentioned on a Atlassian blog page, generate a config file within the .ssh folder, including the following text:

#user1 account
 Host bitbucket.org-user1
     HostName bitbucket.org
     User git
     IdentityFile ~/.ssh/user1
     IdentitiesOnly yes

 #user2 account
 Host bitbucket.org-user2
     HostName bitbucket.org
     User git
     IdentityFile ~/.ssh/user2
     IdentitiesOnly yes

Then you can simply checkout with the suffix domain and within the projects you can configure the author names, etc. locally.

How to convert .pem into .key?

just as a .crt file is in .pem format, a .key file is also stored in .pem format. Assuming that the cert is the only thing in the .crt file (there may be root certs in there), you can just change the name to .pem. The same goes for a .key file. Which means of course that you can rename the .pem file to .key.

Which makes gtrig's answer the correct one. I just thought I'd explain why.

Easy way to concatenate two byte arrays

You can use third party libraries for Clean Code like Apache Commons Lang and use it like:

byte[] bytes = ArrayUtils.addAll(a, b);

How to convert an object to a byte array in C#

Well a cast from myObject to byte[] is never going to work unless you've got an explicit conversion or if myObject is a byte[]. You need a serialization framework of some kind. There are plenty out there, including Protocol Buffers which is near and dear to me. It's pretty "lean and mean" in terms of both space and time.

You'll find that almost all serialization frameworks have significant restrictions on what you can serialize, however - Protocol Buffers more than some, due to being cross-platform.

If you can give more requirements, we can help you out more - but it's never going to be as simple as casting...

EDIT: Just to respond to this:

I need my binary file to contain the object's bytes. Only the bytes, no metadata whatsoever. Packed object-to-object. So I'll be implementing custom serialization.

Please bear in mind that the bytes in your objects are quite often references... so you'll need to work out what to do with them.

I suspect you'll find that designing and implementing your own custom serialization framework is harder than you imagine.

I would personally recommend that if you only need to do this for a few specific types, you don't bother trying to come up with a general serialization framework. Just implement an instance method and a static method in all the types you need:

public void WriteTo(Stream stream)
public static WhateverType ReadFrom(Stream stream)

One thing to bear in mind: everything becomes more tricky if you've got inheritance involved. Without inheritance, if you know what type you're starting with, you don't need to include any type information. Of course, there's also the matter of versioning - do you need to worry about backward and forward compatibility with different versions of your types?

In Java, what does NaN mean?

NaN means "Not a number." It's a special floating point value that means that the result of an operation was not defined or not representable as a real number.

See here for more explanation of this value.

Writing to a file in a for loop

That is because you are opening , writing and closing the file 10 times inside your for loop

myfile = open('xyz.txt', 'w')
myfile.writelines(var1)
myfile.close()

You should open and close your file outside for loop.

myfile = open('xyz.txt', 'w')
for line in lines:
    var1, var2 = line.split(",");
    myfile.write("%s\n" % var1)

myfile.close()
text_file.close()

You should also notice to use write and not writelines.

writelines writes a list of lines to your file.

Also you should check out the answers posted by folks here that uses with statement. That is the elegant way to do file read/write operations in Python

How to pass arguments to Shell Script through docker run

Use the same file.sh

#!/bin/bash
echo $1

Build the image using the existing Dockerfile:

docker build -t test .

Run the image with arguments abc or xyz or something else.

docker run -ti --rm test /file.sh abc

docker run -ti --rm test /file.sh xyz

CS1617: Invalid option ‘6’ for /langversion; must be ISO-1, ISO-2, 3, 4, 5 or Default

In my case the error message was:

ASPNETCOMPILER : error CS1617: Invalid option '7.3' for /langversion; must be ISO-1, ISO-2, Default or an integer in range 1 to 6.

As stated in this GitHub issue, and this VS Developer Community post it seems to be a bug in an older Microsoft.CodeDom.Providers.DotNetCompilerPlatform NuGet package.

After upgrading this NuGet package to 3.6.0 the error still persisted in my web application.

Solution

I found out that I had to delete an old "bin\Roslyn" folder in my Web Application to make this work.

It seems that the newer Microsoft.CodeDom.Providers.DotNetCompilerPlatform NuGet package (3.6.0 in my case) does not bring a its own "Rosyln" folder anymore, and if present, that old "Roslyn" folder took precedence during compilation.

HTML table with fixed headers and a fixed column?

The jQuery DataTables plug-in is one excellent way to achieve excel-like fixed column(s) and headers.

Note the examples section of the site and the "extras".
http://datatables.net/examples/
http://datatables.net/extras/

The "Extras" section has tools for fixed columns and fixed headers.

Fixed Columns
http://datatables.net/extras/fixedcolumns/
(I believe the example on this page is the one most appropriate for your question.)

Fixed Header
http://datatables.net/extras/fixedheader/
(Includes an example with a full page spreadsheet style layout: http://datatables.net/release-datatables/extras/FixedHeader/top_bottom_left_right.html)

Query to display all tablespaces in a database and datafiles

SELECT a.file_name,
       substr(A.tablespace_name,1,14) tablespace_name,
       trunc(decode(A.autoextensible,'YES',A.MAXSIZE-A.bytes+b.free,'NO',b.free)/1024/1024) free_mb,
       trunc(a.bytes/1024/1024) allocated_mb,
       trunc(A.MAXSIZE/1024/1024) capacity,
       a.autoextensible ae
FROM (
     SELECT file_id, file_name,
            tablespace_name,
            autoextensible,
            bytes,
            decode(autoextensible,'YES',maxbytes,bytes) maxsize
     FROM   dba_data_files
     GROUP BY file_id, file_name,
              tablespace_name,
              autoextensible,
              bytes,
              decode(autoextensible,'YES',maxbytes,bytes)
     ) a,
     (SELECT file_id,
             tablespace_name,
             sum(bytes) free
      FROM   dba_free_space
      GROUP BY file_id,
               tablespace_name
      ) b
WHERE a.file_id=b.file_id(+)
AND A.tablespace_name=b.tablespace_name(+)
ORDER BY A.tablespace_name ASC; 

What should be the package name of android app?

As stated here: Package names are written in all lower case to avoid conflict with the names of classes or interfaces.

Companies use their reversed Internet domain name to begin their package names—for example, com.example.mypackage for a package named mypackage created by a programmer at example.com.

Name collisions that occur within a single company need to be handled by convention within that company, perhaps by including the region or the project name after the company name (for example, com.example.region.mypackage).

Packages in the Java language itself begin with java. or javax.

In some cases, the internet domain name may not be a valid package name. This can occur if the domain name contains a hyphen or other special character, if the package name begins with a digit or other character that is illegal to use as the beginning of a Java name, or if the package name contains a reserved Java keyword, such as "int". In this event, the suggested convention is to add an underscore. For example:

enter image description here

Java 8 - Best way to transform a list: map or foreach?

If you use Eclipse Collections you can use the collectIf() method.

MutableList<Integer> source =
    Lists.mutable.with(1, null, 2, null, 3, null, 4, null, 5);

MutableList<String> result = source.collectIf(Objects::nonNull, String::valueOf);

Assert.assertEquals(Lists.immutable.with("1", "2", "3", "4", "5"), result);

It evaluates eagerly and should be a bit faster than using a Stream.

Note: I am a committer for Eclipse Collections.

What, exactly, is needed for "margin: 0 auto;" to work?

It will also work with display:table - a useful display property in this case because it doesn't require a width to be set. (I know this post is 5 years old, but it's still relevant to passers-by ;)

IIS 500.19 with 0x80070005 The requested page cannot be accessed because the related configuration data for the page is invalid error

I too had the similar issue and i fixed it by commenting some sections in web.config file.

The project was earlier built and deployed in .Net 2.0. After migrating to .Net 3.5, it started throwing the exception.

Resolutions:

If your configuration file contains "<sectionGroup name="system.web.extensions>", comment it and run as this section is already available under Machine.config.

Angular 2 declaring an array of objects

I assume you're using typescript.

To be extra cautious you can define your type as an array of objects that need to match certain interface:

type MyArrayType = Array<{id: number, text: string}>;

const arr: MyArrayType = [
    {id: 1, text: 'Sentence 1'},
    {id: 2, text: 'Sentence 2'},
    {id: 3, text: 'Sentence 3'},
    {id: 4, text: 'Sentenc4 '},
];

Or short syntax without defining a custom type:

const arr: Array<{id: number, text: string}> = [...];

Web colors in an Android color xml resource file

Mostly used colors in Android

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="colorPrimary">#fa3d2f</color>
    <color name="colorPrimaryDark">#d9221f</color>
    <color name="colorAccent">#FF4081</color>

    <!-- Android -->
    <color name="myPrimaryColor">#4688F2</color>
    <color name="myPrimaryDarkColor">#366AD3</color>
    <color name="myAccentColor">#FF9800</color>
    <color name="myDrawerBackground">#F2F2F2</color>
    <color name="myWindowBackground">#DEDEDE</color>
    <color name="myTextPrimaryColor">#000000</color>
    <color name="myNavigationColor">#000000</color>

    <color name="dim_gray">#696969</color>

    <color name="white">#ffffff</color>

    <color name="cetagory_item_bg_01">#ffffff</color>
    <color name="cetagory_item_bg_02">#d3dce5</color>
    <color name="cetagory_item_bg_03">#aecce8</color>
    <color name="cetagory_item_more_bg">#88add9</color>

    <color name="item_details_fragment_bg">#ededed</color>
    <!-- common -->
    <color name="common_white_1">#ffffff</color>
    <color name="common_white_2">#feffff</color>
    <color name="common_white_30">#4dffffff</color>
    <color name="common_white_10">#1aFFFFFF</color>
    <color name="common_gray_txt">#514e4e</color>
    <color name="common_gray_bg">#9fa0a0</color>
    <color name="common_black_10">#1a000000</color>
    <color name="common_black_30_1">#4d000000</color>
    <color name="common_black_30_2">#4d010000</color>
    <color name="common_black_50">#80000000</color>
    <color name="common_black_70">#B3000000</color>
    <color name="common_black_15">#26000000</color>
    <color name="common_red">#ed2024</color>
    <color name="common_yellow">#fff51e</color>
    <color name="common_light_gray_txt">#b9b9ba</color>
    <color name="indicator_gray">#737172</color>
    <color name="common_red_txt">#ff4141</color>
    <color name="common_blue_bg">#0055bd</color>
    <color name="fragment_bg">#efefef</color>
    <color name="main_gray_color">#9d9e9e</color>
    <color name="hint_color">#ababac</color>
    <color name="troubleshooting_txt_color">#231815</color>
    <color name="common_sc_main_color">#0055bd</color>
    <color name="common_ec_blue_txt">#0055bd</color>

    <color name="main_dark">#000000</color>
    <color name="introduction_text">#9FA0A0</color>
    <color name="orange">#FFB600</color>
    <color name="btn_login_email_pressed">#ccFFB600</color>
    <color name="text_dark">#9FA0A0</color>
    <color name="btn_login_facebook">#2E5DAC</color>
    <color name="btn_login_facebook_pressed">#802E5DAC</color>
    <color name="btn_login_twitter">#59ADEC</color>
    <color name="btn_login_twitter_pressed">#8059ADEC</color>
    <color name="spinner_background">#808080</color>
    <color name="clock_remain">#3d3939</color>
    <color name="border_bottom">#C9CACA</color>
    <color name="dash_border">#C9CACA</color>
    <color name="date_color">#b5b5b6</color>

    <!--send trouble shooting-->
    <color name="send_trouble_back_ground">#eae9e8</color>
    <color name="send_trouble_background_header">#cccccc</color>
    <color name="send_trouble_text_color_header">#666666</color>
    <color name="send_trouble_edit_text_color_boder">#c4c3c3</color>
    <color name="send_trouble_bg">#9fa0a0</color>

    <!--copy code-->
    <color name="back_ground_dialog">#90000000</color>



    <!--ec detail product-->
    <color name="ec_btn_go_to_shop_page_off">#0055bd</color>
    <color name="ec_btn_go_to_shop_page_on">#800055bd</color>
    <color name="ec_btn_go_to_detail_page_on">#80FFFFFF</color>
    <color name="ec_btn_login_facebook_off">#2675d7</color>
    <color name="ec_btn_login_facebook_on">#802675d7</color>
    <color name="ec_btn_login_twitter_on">#8044baff</color>
    <color name="ec_btn_login_twitter_off">#44baff</color>
    <color name="ec_btn_login_email_on">#80ffffff</color>
    <color name="ec_btn_login_email_off">#ffffff</color>
    <color name="ec_text_login_email">#ff5500</color>

    <color name="ec_point_manager_text_chart">#0063dd</color>
    <color name="common_green">#45cc28</color>
    <color  name="green1">#139E91</color>
    <color name="blacklight">#212121</color>
    <color name="black_opacity_60">#99000000</color>
    <color name="white_50_percent_opacity">#7fffffff</color>
    <color name="line_config">#c9caca</color>

    <color name="black_semi_transparent">#B2000000</color>
    <color name="background">#e5e5e5</color>
    <color name="half_black">#808080</color>
    <color name="white_pressed">#f1f1f1</color>
    <color name="pink">#e91e63</color>
    <color name="pink_pressed">#ec407a</color>
    <color name="blue_semi_transparent">#805677fc</color>
    <color name="blue_semi_transparent_pressed">#80738ffe</color>
    <color name="black">#000000</color>
    <color name="gray">#A9A9A9</color>
    <color name="nav_header_background">#fdfdfe</color>
    <color name="video_thumbnail_placeholder_color">#d3d3d3</color>
    <color name="video_des_background_color">#cec8c8</color>
</resources>

SOAP vs REST (differences)

REST vs SOAP is not the right question to ask.

REST, unlike SOAP is not a protocol.

REST is an architectural style and a design for network-based software architectures.

REST concepts are referred to as resources. A representation of a resource must be stateless. It is represented via some media type. Some examples of media types include XML, JSON, and RDF. Resources are manipulated by components. Components request and manipulate resources via a standard uniform interface. In the case of HTTP, this interface consists of standard HTTP ops e.g. GET, PUT, POST, DELETE.

@Abdulaziz's question does illuminate the fact that REST and HTTP are often used in tandem. This is primarily due to the simplicity of HTTP and its very natural mapping to RESTful principles.

Fundamental REST Principles

Client-Server Communication

Client-server architectures have a very distinct separation of concerns. All applications built in the RESTful style must also be client-server in principle.

Stateless

Each client request to the server requires that its state be fully represented. The server must be able to completely understand the client request without using any server context or server session state. It follows that all state must be kept on the client.

Cacheable

Cache constraints may be used, thus enabling response data to be marked as cacheable or not-cacheable. Any data marked as cacheable may be reused as the response to the same subsequent request.

Uniform Interface

All components must interact through a single uniform interface. Because all component interaction occurs via this interface, interaction with different services is very simple. The interface is the same! This also means that implementation changes can be made in isolation. Such changes, will not affect fundamental component interaction because the uniform interface is always unchanged. One disadvantage is that you are stuck with the interface. If an optimization could be provided to a specific service by changing the interface, you are out of luck as REST prohibits this. On the bright side, however, REST is optimized for the web, hence incredible popularity of REST over HTTP!

The above concepts represent defining characteristics of REST and differentiate the REST architecture from other architectures like web services. It is useful to note that a REST service is a web service, but a web service is not necessarily a REST service.

See this blog post on REST Design Principles for more details on REST and the above stated bullets.

EDIT: update content based on comments

Add default value of datetime field in SQL Server to a timestamp

This works for me...

ALTER TABLE [accounts] 
 ADD [user_registered] DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ;

Format number to always show 2 decimal places

This is how I solve my problem:

parseFloat(parseFloat(floatString).toFixed(2));

Disabling same-origin policy in Safari

Unfortunately, there is no equivalent for Safari and the argument --disable-web-security doesn't work with Safari.

If you have access to the server side application, you can modify the https response headers to allow access. Mainly the Access-Control-Allow-Origin header. Modifying it will allow Safari to access the resource. See https://developer.mozilla.org/en-US/docs/Web/HTTP/Access_control_CORS#Access-Control-Allow-Origin for more information on the response headers that will help.

'Found the synthetic property @panelState. Please include either "BrowserAnimationsModule" or "NoopAnimationsModule" in your application.'

This error message is often misleading.

You may have forgotten to import the BrowserAnimationsModule. But that was not my problem. I was importing BrowserAnimationsModule in the root AppModule, as everyone should do.

The problem was something completely unrelated to the module. I was animating an*ngIf in the component template but I had forgotten to mention it in the @Component.animations for the component class.

@Component({
  selector: '...',
  templateUrl: './...',
  animations: [myNgIfAnimation] // <-- Don't forget!
})

If you use an animation in a template, you also must list that animation in the component's animations metadata ... every time.

Compare 2 arrays which returns difference

I know this is an old question, but I thought I would share this little trick.

var diff = $(old_array).not(new_array).get();

diff now contains what was in old_array that is not in new_array

Set ImageView width and height programmatically?

kotlin

val density = Resources.getSystem().displayMetrics.density
view.layoutParams.height = 20 * density.toInt()

What are the advantages of NumPy over regular Python lists?

Alex mentioned memory efficiency, and Roberto mentions convenience, and these are both good points. For a few more ideas, I'll mention speed and functionality.

Functionality: You get a lot built in with NumPy, FFTs, convolutions, fast searching, basic statistics, linear algebra, histograms, etc. And really, who can live without FFTs?

Speed: Here's a test on doing a sum over a list and a NumPy array, showing that the sum on the NumPy array is 10x faster (in this test -- mileage may vary).

from numpy import arange
from timeit import Timer

Nelements = 10000
Ntimeits = 10000

x = arange(Nelements)
y = range(Nelements)

t_numpy = Timer("x.sum()", "from __main__ import x")
t_list = Timer("sum(y)", "from __main__ import y")
print("numpy: %.3e" % (t_numpy.timeit(Ntimeits)/Ntimeits,))
print("list:  %.3e" % (t_list.timeit(Ntimeits)/Ntimeits,))

which on my systems (while I'm running a backup) gives:

numpy: 3.004e-05
list:  5.363e-04

Skipping error in for-loop

Instead of catching the error, wouldn't it be possible to test in or before the myplotfunction() function first if the error will occur (i.e. if the breaks are unique) and only plot it for those cases where it won't appear?!

Flushing buffers in C

Flushing the output buffers:

printf("Buffered, will be flushed");
fflush(stdout); // Prints to screen or whatever your standard out is

or

fprintf(fd, "Buffered, will be flushed");
fflush(fd);  //Prints to a file

Can be a very helpful technique. Why would you want to flush an output buffer? Usually when I do it, it's because the code is crashing and I'm trying to debug something. The standard buffer will not print everytime you call printf() it waits until it's full then dumps a bunch at once. So if you're trying to check if you're making it to a function call before a crash, it's helpful to printf something like "got here!", and sometimes the buffer hasn't been flushed before the crash happens and you can't tell how far you've really gotten.

Another time that it's helpful, is in multi-process or multi-thread code. Again, the buffer doesn't always flush on a call to a printf(), so if you want to know the true order of execution of multiple processes you should fflush the buffer after every print.

I make a habit to do it, it saves me a lot of headache in debugging. The only downside I can think of to doing so is that printf() is an expensive operation (which is why it doesn't by default flush the buffer).


As far as flushing the input buffer (stdin), you should not do that. Flushing stdin is undefined behavior according to the C11 standard §7.21.5.2 part 2:

If stream points to an output stream ... the fflush function causes any unwritten data for that stream ... to be written to the file; otherwise, the behavior is undefined.

On some systems, Linux being one as you can see in the man page for fflush(), there's a defined behavior but it's system dependent so your code will not be portable.

Now if you're worried about garbage "stuck" in the input buffer you can use fpurge() on that. See here for more on fflush() and fpurge()

Define global variable with webpack

There are several way to approach globals:

  1. Put your variables in a module.

Webpack evaluates modules only once, so your instance remains global and carries changes through from module to module. So if you create something like a globals.js and export an object of all your globals then you can import './globals' and read/write to these globals. You can import into one module, make changes to the object from a function and import into another module and read those changes in a function. Also remember the order things happen. Webpack will first take all the imports and load them up in order starting in your entry.js. Then it will execute entry.js. So where you read/write to globals is important. Is it from the root scope of a module or in a function called later?

config.js

export default {
    FOO: 'bar'
}

somefile.js

import CONFIG from './config.js'
console.log(`FOO: ${CONFIG.FOO}`)

Note: If you want the instance to be new each time, then use an ES6 class. Traditionally in JS you would capitalize classes (as opposed to the lowercase for objects) like
import FooBar from './foo-bar' // <-- Usage: myFooBar = new FooBar()

  1. Webpack's ProvidePlugin

Here's how you can do it using Webpack's ProvidePlugin (which makes a module available as a variable in every module and only those modules where you actually use it). This is useful when you don't want to keep typing import Bar from 'foo' again and again. Or you can bring in a package like jQuery or lodash as global here (although you might take a look at Webpack's Externals).

Step 1) Create any module. For example, a global set of utilities would be handy:

utils.js

export function sayHello () {
  console.log('hello')
}

Step 2) Alias the module and add to ProvidePlugin:

webpack.config.js

var webpack = require("webpack");
var path = require("path");

// ...

module.exports = {

  // ...

  resolve: {
    extensions: ['', '.js'],
    alias: {
      'utils': path.resolve(__dirname, './utils')  // <-- When you build or restart dev-server, you'll get an error if the path to your utils.js file is incorrect.
    }
  },

  plugins: [

    // ...

    new webpack.ProvidePlugin({
      'utils': 'utils'
    })
  ]  

}

Now just call utils.sayHello() in any js file and it should work. Make sure you restart your dev-server if you are using that with Webpack.

Note: Don't forget to tell your linter about the global, so it won't complain. For example, see my answer for ESLint here.

  1. Use Webpack's DefinePlugin

If you just want to use const with string values for your globals, then you can add this plugin to your list of Webpack plugins:

new webpack.DefinePlugin({
  PRODUCTION: JSON.stringify(true),
  VERSION: JSON.stringify("5fa3b9"),
  BROWSER_SUPPORTS_HTML5: true,
  TWO: "1+1",
  "typeof window": JSON.stringify("object")
})

Use it like:

console.log("Running App version " + VERSION);
if(!BROWSER_SUPPORTS_HTML5) require("html5shiv");
  1. Use the global window object (or Node's global)

window.foo = 'bar'  // For SPA's, browser environment.
global.foo = 'bar'  // Webpack will automatically convert this to window if your project is targeted for web (default), read more here: https://webpack.js.org/configuration/node/

You'll see this commonly used for polyfills, for example: window.Promise = Bluebird

  1. Use a package like dotenv

(For server side projects) The dotenv package will take a local configuration file (which you could add to your .gitignore if there are any keys/credentials) and adds your configuration variables to Node's process.env object.

// As early as possible in your application, require and configure dotenv.    
require('dotenv').config()

Create a .env file in the root directory of your project. Add environment-specific variables on new lines in the form of NAME=VALUE. For example:

DB_HOST=localhost
DB_USER=root
DB_PASS=s1mpl3

That's it.

process.env now has the keys and values you defined in your .env file.

var db = require('db')
db.connect({
  host: process.env.DB_HOST,
  username: process.env.DB_USER,
  password: process.env.DB_PASS
})

Notes:

Regarding Webpack's Externals, use it if you want to exclude some modules from being included in your built bundle. Webpack will make the module globally available but won't put it in your bundle. This is handy for big libraries like jQuery (because tree shaking external packages doesn't work in Webpack) where you have these loaded on your page already in separate script tags (perhaps from a CDN).

Await operator can only be used within an Async method

You can only use await in an async method, and Main cannot be async.

You'll have to use your own async-compatible context, call Wait on the returned Task in the Main method, or just ignore the returned Task and just block on the call to Read. Note that Wait will wrap any exceptions in an AggregateException.

If you want a good intro, see my async/await intro post.

What is the convention in JSON for empty vs. null?

There is the question whether we want to differentiate between cases:

  1. "phone" : "" = the value is empty

  2. "phone" : null = the value for "phone" was not set yet

If we want differentiate I would use null for this. Otherwise we would need to add a new field like "isAssigned" or so. This is an old Database issue.

Get values from other sheet using VBA

Try

 ThisWorkbook.Sheets("name of sheet 2").Range("A1")

to access a range in sheet 2 independently of where your code is or which sheet is currently active. To make sheet 2 the active sheet, try

 ThisWorkbook.Sheets("name of sheet 2").Activate

If you just need the sum of a row in a different sheet, there is no need for using VBA at all. Enter a formula like this in sheet 1:

=SUM([Name-Of-Sheet2]!A1:D1)

How do I generate random integers within a specific range in Java?

Using Java 8 Streams,

  • Pass the initialCapacity - How many numbers
  • Pass the randomBound - from x to randomBound
  • Pass true/false for sorted or not
  • Pass an new Random() object

 

public static List<Integer> generateNumbers(int initialCapacity, int randomBound, Boolean sorted, Random random) {

    List<Integer> numbers = random.ints(initialCapacity, 1, randomBound).boxed().collect(Collectors.toList());

    if (sorted)
        numbers.sort(null);

    return numbers;
}

It generates numbers from 1-Randombound in this example.

Java: Simplest way to get last word in a string

You can do that with StringUtils (from Apache Commons Lang). It avoids index-magic, so it's easier to understand. Unfortunately substringAfterLast returns empty string when there is no separator in the input string so we need the if statement for that case.

public static String getLastWord(String input) {
    String wordSeparator = " ";
    boolean inputIsOnlyOneWord = !StringUtils.contains(input, wordSeparator);
    if (inputIsOnlyOneWord) {
        return input;
    }
    return StringUtils.substringAfterLast(input, wordSeparator);
}

Building executable jar with maven?

The answer of Pascal Thivent helped me out, too. But if you manage your plugins within the <pluginManagement>element, you have to define the assembly again outside of the plugin management, or else the dependencies are not packed in the jar if you run mvn install.

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <version>1.0.0-SNAPSHOT</version>
    <packaging>jar</packaging>


    <build>
        <pluginManagement>
            <plugins>

                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-compiler-plugin</artifactId>
                    <version>3.1</version>
                    <configuration>
                        <source>1.6</source>
                        <target>1.6</target>
                    </configuration>
                </plugin>

                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-assembly-plugin</artifactId>
                    <version>2.4</version>
                    <configuration>
                        <archive>
                            <manifest>
                                <mainClass>main.App</mainClass>
                            </manifest>
                        </archive>
                        <descriptorRefs>
                            <descriptorRef>jar-with-dependencies</descriptorRef>
                        </descriptorRefs>
                    </configuration>
                    <executions>
                        <execution>
                            <id>make-assembly</id>
                            <phase>package</phase>
                            <goals>
                                <goal>single</goal>
                            </goals>
                        </execution>
                    </executions>
                </plugin>

            </plugins>

        </pluginManagement>

        <plugins> <!-- did NOT work without this  -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-assembly-plugin</artifactId>
            </plugin>
        </plugins>

    </build>


    <dependencies>
       <!--  dependencies commented out to shorten example -->
    </dependencies>

</project>

How to get Tensorflow tensor dimensions (shape) as int values?

2.0 Compatible Answer: In Tensorflow 2.x (2.1), you can get the dimensions (shape) of the tensor as integer values, as shown in the Code below:

Method 1 (using tf.shape):

import tensorflow as tf
c = tf.constant([[1.0, 2.0, 3.0], [4.0, 5.0, 6.0]])
Shape = c.shape.as_list()
print(Shape)   # [2,3]

Method 2 (using tf.get_shape()):

import tensorflow as tf
c = tf.constant([[1.0, 2.0, 3.0], [4.0, 5.0, 6.0]])
Shape = c.get_shape().as_list()
print(Shape)   # [2,3]

How add class='active' to html menu with php

  1. $page='one' should occur before you require_once() not after. After is too late- the code has already been required, and $nav has already been defined.

  2. You should use include('header.php'); and include('footer.php'); instead of setting a $nav variable early on. That increases flexibility.

  3. Make more functions. Something like this really makes things easier to follow:

    function maybe($x,$y){return $x?$y:'';}
    function aclass($k){return " class=\"$k\" "; }
    

    then you can write your "condition" like this:

    <a href="..." <?= maybe($page=='one',aclass('active')) ?>> ....
    

SSL_connect: SSL_ERROR_SYSCALL in connection to github.com:443

I have a similar issue and I just found that in my case it may be the antivirus that creates an issue.

At some moment I've got the same error while trying to pull some data from github.com.

I knew that Kaspersky is intercepting the SSL connections to check for malicious content from the sites and I decided to disable it, but I found that KAV is hung and not really responding, so I just closed Kaspersky and tried to connect to github.com again and alas! I was able to connect successfully to GitHub.

So in you case it may be a similar issue.

How to sort a data frame by alphabetic order of a character variable in R?

The arrange function in the plyr package makes it easy to sort by multiple columns. For example, to sort DF by ID first and then decreasing by num, you can write

plyr::arrange(DF, ID, desc(num))

What is a practical use for a closure in JavaScript?

In the JavaScript (or any ECMAScript) language, in particular, closures are useful in hiding the implementation of functionality while still revealing the interface.

For example, imagine you are writing a class of date utility methods and you want to allow users to look up weekday names by index, but you don't want them to be able to modify the array of names you use under the hood.

var dateUtil = {
  weekdayShort: (function() {
    var days = ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun'];
    return function(x) {
      if ((x != parseInt(x)) || (x < 1) || (x > 7)) {
        throw new Error("invalid weekday number");
      }
      return days[x - 1];
    };
  }())
};

Note that the days array could simply be stored as a property of the dateUtil object, but then it would be visible to users of the script and they could even change it if they wanted, without even needing your source code. However, since it's enclosed by the anonymous function which returns the date lookup function it is only accessible by the lookup function so it is now tamperproof.

How to set the max value and min value of <input> in html5 by javascript or jquery?

Try this

 $(function(){
   $("input[type='number']").prop('min',1);
   $("input[type='number']").prop('max',10);
});

Demo

Where's the DateTime 'Z' format specifier?

Label1.Text = dt.ToString("dd MMM yyyy | hh:mm | ff | zzz | zz | z");

will output:

07 Mai 2009 | 08:16 | 13 | +02:00 | +02 | +2

I'm in Denmark, my Offset from GMT is +2 hours, witch is correct.

if you need to get the CLIENT Offset, I recommend that you check a little trick that I did. The Page is in a Server in UK where GMT is +00:00 and, as you can see you will get your local GMT Offset.


Regarding you comment, I did:

DateTime dt1 = DateTime.Now;
DateTime dt2 = dt1.ToUniversalTime();

Label1.Text = dt1.ToString("dd MMM yyyy | hh:mm | ff | zzz | zz | z");
Label2.Text = dt2.ToString("dd MMM yyyy | hh:mm | FF | ZZZ | ZZ | Z");

and I get this:

07 Mai 2009 | 08:24 | 14 | +02:00 | +02 | +2
07 Mai 2009 | 06:24 | 14 | ZZZ | ZZ | Z 

I get no Exception, just ... it does nothing with capital Z :(

I'm sorry, but am I missing something?


Reading carefully the MSDN on Custom Date and Time Format Strings

there is no support for uppercase 'Z'.

XSS filtering function in PHP

Try using for Clean XSS

xss_clean($data): "><script>alert(String.fromCharCode(74,111,104,116,111,32,82,111,98,98,105,101))</script>

Posting raw image data as multipart/form-data in curl

As of PHP 5.6 @$filePath will not work in CURLOPT_POSTFIELDS without CURLOPT_SAFE_UPLOAD being set and it is completely removed in PHP 7. You will need to use a CurlFile object, RFC here.

$fields = [
    'name' => new \CurlFile($filePath, 'image/png', 'filename.png')
];
curl_setopt($resource, CURLOPT_POSTFIELDS, $fields);

How do I get the computer name in .NET

Try this one.

public static string GetFQDN()
{
    string domainName = NetworkInformation.IPGlobalProperties.GetIPGlobalProperties().DomainName;
    string hostName = Dns.GetHostName();
    string fqdn;
    if (!hostName.Contains(domainName))
        fqdn = hostName + "." +domainName;
    else
        fqdn = hostName;

    return fqdn;
}

Update multiple rows using select statement

I have used this one on MySQL, MS Access and SQL Server. The id fields are the fields on wich the tables coincide, not necesarily the primary index.

UPDATE DestTable INNER JOIN SourceTable ON DestTable.idField = SourceTable.idField SET DestTable.Field1 = SourceTable.Field1, DestTable.Field2 = SourceTable.Field2...

Reading a date using DataReader

If the query's column has an appropriate type then

var dateString = MyReader.GetDateTime(MyReader.GetOrdinal("column")).ToString(myDateFormat)

If the query's column is actually a string then see other answers.

Reset MySQL root password using ALTER USER statement after install on Mac

If this is NOT your first time setting up the password, try this method:

mysql> UPDATE mysql.user SET Password=PASSWORD('your_new_password')
           WHERE User='root'; 

And if you get the following error, there is a high chance that you have never set your password before:

ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement. 

To set up your password for the first time:

mysql> SET PASSWORD = PASSWORD('your_new_password');
Query OK, 0 rows affected, 1 warning (0.01 sec)

Reference: https://dev.mysql.com/doc/refman/5.6/en/alter-user.html

Why maven? What are the benefits?

Figuring out package dependencies is really not that hard. You rarely do it anyway. Probably once during project setup and few more during upgrades. With maven you'll end up fixing mismatched dependencies, badly written poms, and doing package exclusions anyway.

Not that hard... for toy projects. But the projects I work on have many, really many, of them, and I'm very glad to get them transitively, to have a standardized naming scheme for them. Managing all this manually by hand would be a nightmare.

And yes, sometimes you have to work on the convergence of dependencies. But think about it twice, this is not inherent to Maven, this is inherent to any system using dependencies (and I am talking about Java dependencies in general here).

So with Ant, you have to do the same work except that you have to do everything manually: grabbing some version of project A and its dependencies, grabbing some version of project B and its dependencies, figuring out yourself what exact versions they use, checking that they don't overlap, checking that they are not incompatible, etc. Welcome to hell.

On the other hand, Maven supports dependency management and will retrieve them transitively for me and gives me the tooling I need to manage the complexity inherent to dependency management: I can analyze a dependency tree, control the versions used in transitive dependencies, exclude some of them if required, control the converge across modules, etc. There is no magic. But at least you have support.

And don't forget that dependency management is only a small part of what Maven offers, there is much more (not even mentioning the other tools that integrates nicely with Maven, e.g. Sonar).

Slow FIX-COMPILE-DEPLOY-DEBUG cycle, which kills productivity. This is my main gripe. You make a change, the you have to wait for maven build to kick in and wait for it to deploy. No hot deployment whatsoever.

First, why do you use Maven like this? I don't. I use my IDE to write tests, code until they pass, refactor, deploy, hot deploy and run a local Maven build when I'm done, before to commit, to make sure I will not break the continuous build.

Second, I'm not sure using Ant would make things much better. And to my experience, modular Maven builds using binary dependencies gives me faster build time than typical monolithic Ant builds. Anyway, have a look at Maven Shell for a ready to (re)use Maven environment (which is awesome by the way).

So at end, and I'm sorry to say so, it's not really Maven that is killing your productivity, it's you misusing your tools. And if you're not happy with it, well, what can I say, don't use it. Personally, I'm using Maven since 2003 and I never looked back.

How to get http headers in flask?

just note, The different between the methods are, if the header is not exist

request.headers.get('your-header-name')

will return None or no exception, so you can use it like

if request.headers.get('your-header-name'):
    ....

but the following will throw an error

if request.headers['your-header-name'] # KeyError: 'your-header-name'
    ....

You can handle it by

if 'your-header-name' in request.headers:
   customHeader = request.headers['your-header-name']
   ....

How do I run a shell script without using "sh" or "bash" commands?

These are the prerequisites of directly using the script name:

  1. Add the shebang line (#!/bin/bash) at the very top.
  2. Use chmod u+x scriptname to make the script executable (where scriptname is the name of your script).
  3. Place the script under /usr/local/bin folder.
    • Note: I suggest placing it under /usr/local/bin because most likely that path will be already added to your PATH variable.
  4. Run the script using just its name, scriptname.

If you don't have access to /usr/local/bin then do the following:

  1. Create a folder in your home directory and call it bin.

  2. Do ls -lA on your home directory, to identify the start-up script your shell is using. It should be either .profile or .bashrc.

  3. Once you have identified the start up script, add the following line:

    PATH="$PATH:$HOME/bin"
    
  4. Once added, source your start-up script or log out and log back in.

    To source, put . followed by a space and then your start-up script name, e.g. . .profile or . .bashrc

  5. Run the script using just its name, scriptname.

Real-world examples of recursion

Feedback loops in a hierarchical organization.

Top boss tells top executives to collect feedback from everyone in the company.

Each executive gathers his/her direct reports and tells them to gather feedback from their direct reports.

And on down the line.

People with no direct reports -- the leaf nodes in the tree -- give their feedback.

The feedback travels back up the tree with each manager adding his/her own feedback.

Eventually all the feedback makes it back up to the top boss.

This is the natural solution because the recursive method allows filtering at each level -- the collating of duplicates and the removal of offensive feedback. The top boss could send a global email and have each employee report feedback directly back to him/her, but there are the "you can't handle the truth" and the "you're fired" problems, so recursion works best here.

Extracting date from a string in Python

For extracting the date from a string in Python; the best module available is the datefinder module.

You can use it in your Python project by following the easy steps given below.

Step 1: Install datefinder Package

pip install datefinder

Step 2: Use It In Your Project

import datefinder

input_string = "monkey 2010-07-10 love banana"
# a generator will be returned by the datefinder module. I'm typecasting it to a list. Please read the note of caution provided at the bottom.
matches = list(datefinder.find_dates(input_string))

if len(matches) > 0:
    # date returned will be a datetime.datetime object. here we are only using the first match.
    date = matches[0]
    print date
else:
    print 'No dates found'

note: if you are expecting a large number of matches; then typecasting to list won't be a recommended way as it will be having a big performance overhead.

Why would anybody use C over C++?

I haven't been able to find much evidence as to why you would want to choose C over C++.

You can hardly call what I'm about to say evidence; it's just my opinion.

People like C because it fits nicely inside the mind of the prgrammer.

There are many complex rules of C++ [when do you need virtual destructors, when can you call virtual methods in a constructor, how does overloading and overriding interact, ...], and to master them all takes a lot of effort. Also, between references, operator overloading and function overloading, understanding a piece of code can require you to understand other code that may or may not be easy to find.

A different question in why organizations would prefer C over C++. I don't know that, I'm just a people ;-)

In the defense of C++, it does bring valuable features to the table; the one I value most is probably parametric('ish) polymorphism, though: operations and types that takes one or more types as arguments.

Implement touch using Python?

write_text() from pathlib.Path can be used.

>>> from pathlib import Path
>>> Path('aa.txt').write_text("")
0

How to add form validation pattern in Angular 2?

Since version 2.0.0-beta.8 (2016-03-02), Angular now includes a Validators.pattern regex validator.

See the CHANGELOG

Using Google Translate in C#

When I used above code.It show me translated text as question mark like (???????).Then I convert from WebClient to HttpClient then I got a accurate result.So you can used code like this.

public static string TranslateText( string input, string languagePair)       
{
    string url = String.Format("http://www.google.com/translate_t?hl=en&ie=UTF8&text={0}&langpair={1}", input, languagePair);
    HttpClient httpClient = new HttpClient();
    string result = httpClient.GetStringAsync(url).Result;
    result = result.Substring(result.IndexOf("<span title=\"") + "<span title=\"".Length);
    result = result.Substring(result.IndexOf(">") + 1);
    result = result.Substring(0, result.IndexOf("</span>"));
    return result.Trim();
}

Then you Call a function like.You put first two letter of any language pair.

From English(en) To Urdu(ur).

TranslateText(line, "en|ur")

How to write LaTeX in IPython Notebook?

IPython notebook uses MathJax to render LaTeX inside html/markdown. Just put your LaTeX math inside $$.

$$c = \sqrt{a^2 + b^2}$$

sqrt

Or you can display LaTeX / Math output from Python, as seen towards the end of the notebook tour:

from IPython.display import display, Math, Latex
display(Math(r'F(k) = \int_{-\infty}^{\infty} f(x) e^{2\pi i k} dx'))

integral

Count the cells with same color in google spreadsheet

The previous functions didn't work for me, so I've made another function that use the same logic of one of the answers above: parse the formula in the cell to find the referenced range of cells to examine and than look for the coloured cells. You can find a detailed description here: Google Script count coloured with reference, but the code is below:

function countColoured(reference) {
  var sheet = SpreadsheetApp.getActiveSheet();
  var formula = SpreadsheetApp.getActiveRange().getFormula();
  var args = formula.match(/=\w+\((.*)\)/i)[1].split('!');
  try {
    if (args.length == 1) {
      var range = sheet.getRange(args[0]);
    }
    else {
      sheet = ss.getSheetByName(args[0].replace(/'/g, ''));
      range = sheet.getRange(args[1]);
    }
  }
  catch(e) {
    throw new Error(args.join('!') + ' is not a valid range');
  }
  var c = 0;
  var numRows = range.getNumRows();
  var numCols = range.getNumColumns();
  for (var i = 1; i <= numRows; i++) {
    for (var j = 1; j <= numCols; j++) {
      c = c + ( range.getCell(i,j).getBackground() == "#ffffff" ? 0 : 1 );
    }
  }
  return c > 0 ? c : "" ;
}

How to add a bot to a Telegram Group?

You have to use @BotFather, send it command: /setjoingroups There will be dialog like this:

YOU: /setjoingroups

BotFather: Choose a bot to change group membership settings.

YOU: @YourBot

BotFather: 'Enable' - bot can be added to groups. 'Disable' - block group invitations, the bot can't be added to groups. Current status is: DISABLED

YOU: Enable

BotFather: Success! The new status is: ENABLED.

After this you will see button "Add to Group" in your bot's profile.

Regex to check with starts with http://, https:// or ftp://

You need a whole input match here.

System.out.println(test.matches("^(http|https|ftp)://.*$")); 

Edit:(Based on @davidchambers's comment)

System.out.println(test.matches("^(https?|ftp)://.*$")); 

Java Delegates?

No, but they're fakeable using proxies and reflection:

  public static class TestClass {
      public String knockKnock() {
          return "who's there?";
      }
  }

  private final TestClass testInstance = new TestClass();

  @Test public void
  can_delegate_a_single_method_interface_to_an_instance() throws Exception {
      Delegator<TestClass, Callable<String>> knockKnockDelegator = Delegator.ofMethod("knockKnock")
                                                                   .of(TestClass.class)
                                                                   .to(Callable.class);
      Callable<String> callable = knockKnockDelegator.delegateTo(testInstance);
      assertThat(callable.call(), is("who's there?"));
  }

The nice thing about this idiom is that you can verify that the delegated-to method exists, and has the required signature, at the point where you create the delegator (although not at compile-time, unfortunately, although a FindBugs plug-in might help here), then use it safely to delegate to various instances.

See the karg code on github for more tests and implementation.

HTML form with two submit buttons and two "target" attributes

HTML:

<form method="get">
<input type="text" name="id" value="123"/>
<input type="submit" name="action" value="add"/>
<input type="submit" name="action" value="delete"/>
</form>

JS:

$('form').submit(function(ev){ 
ev.preventDefault();
console.log('clicked',ev.originalEvent,ev.originalEvent.explicitOriginalTarget) 
})

http://jsfiddle.net/arzo/unhc3/

adding 30 minutes to datetime php/mysql

Try this one

DATE_ADD(datefield, INTERVAL 30 MINUTE)

Difference between a user and a schema in Oracle?

A schema and database users are same but if schema has owned database objects and they can do anything their object but user just access the objects, They can't DO any DDL operations until schema user give you the proper privileges.

Checking if a file is a directory or just a file

You can call the stat() function and use the S_ISREG() macro on the st_mode field of the stat structure in order to determine if your path points to a regular file:

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

int is_regular_file(const char *path)
{
    struct stat path_stat;
    stat(path, &path_stat);
    return S_ISREG(path_stat.st_mode);
}

Note that there are other file types besides regular and directory, like devices, pipes, symbolic links, sockets, etc. You might want to take those into account.

Check whether a string contains a substring

Case Insensitive Substring Example

This is an extension of Eugene's answer, which converts the strings to lower case before checking for the substring:

if (index(lc($str), lc($substr)) != -1) {
    print "$str contains $substr\n";
} 

How to define the css :hover state in a jQuery selector?

You can try this:

$(".myclass").mouseover(function() {
    $(this).find(" > div").css("background-color","red");
}).mouseout(function() {
    $(this).find(" > div").css("background-color","transparent");
});

DEMO

Can't execute jar- file: "no main manifest attribute"

Try this command to include the jar:

java -cp yourJarName.jar your.package..your.MainClass

Python: How would you save a simple settings/config file?

ConfigParser Basic example

The file can be loaded and used like this:

#!/usr/bin/env python

import ConfigParser
import io

# Load the configuration file
with open("config.yml") as f:
    sample_config = f.read()
config = ConfigParser.RawConfigParser(allow_no_value=True)
config.readfp(io.BytesIO(sample_config))

# List all contents
print("List all contents")
for section in config.sections():
    print("Section: %s" % section)
    for options in config.options(section):
        print("x %s:::%s:::%s" % (options,
                                  config.get(section, options),
                                  str(type(options))))

# Print some contents
print("\nPrint some contents")
print(config.get('other', 'use_anonymous'))  # Just get the value
print(config.getboolean('other', 'use_anonymous'))  # You know the datatype?

which outputs

List all contents
Section: mysql
x host:::localhost:::<type 'str'>
x user:::root:::<type 'str'>
x passwd:::my secret password:::<type 'str'>
x db:::write-math:::<type 'str'>
Section: other
x preprocessing_queue:::["preprocessing.scale_and_center",
"preprocessing.dot_reduction",
"preprocessing.connect_lines"]:::<type 'str'>
x use_anonymous:::yes:::<type 'str'>

Print some contents
yes
True

As you can see, you can use a standard data format that is easy to read and write. Methods like getboolean and getint allow you to get the datatype instead of a simple string.

Writing configuration

import os
configfile_name = "config.yaml"

# Check if there is already a configurtion file
if not os.path.isfile(configfile_name):
    # Create the configuration file as it doesn't exist yet
    cfgfile = open(configfile_name, 'w')

    # Add content to the file
    Config = ConfigParser.ConfigParser()
    Config.add_section('mysql')
    Config.set('mysql', 'host', 'localhost')
    Config.set('mysql', 'user', 'root')
    Config.set('mysql', 'passwd', 'my secret password')
    Config.set('mysql', 'db', 'write-math')
    Config.add_section('other')
    Config.set('other',
               'preprocessing_queue',
               ['preprocessing.scale_and_center',
                'preprocessing.dot_reduction',
                'preprocessing.connect_lines'])
    Config.set('other', 'use_anonymous', True)
    Config.write(cfgfile)
    cfgfile.close()

results in

[mysql]
host = localhost
user = root
passwd = my secret password
db = write-math

[other]
preprocessing_queue = ['preprocessing.scale_and_center', 'preprocessing.dot_reduction', 'preprocessing.connect_lines']
use_anonymous = True

XML Basic example

Seems not to be used at all for configuration files by the Python community. However, parsing / writing XML is easy and there are plenty of possibilities to do so with Python. One is BeautifulSoup:

from BeautifulSoup import BeautifulSoup

with open("config.xml") as f:
    content = f.read()

y = BeautifulSoup(content)
print(y.mysql.host.contents[0])
for tag in y.other.preprocessing_queue:
    print(tag)

where the config.xml might look like this

<config>
    <mysql>
        <host>localhost</host>
        <user>root</user>
        <passwd>my secret password</passwd>
        <db>write-math</db>
    </mysql>
    <other>
        <preprocessing_queue>
            <li>preprocessing.scale_and_center</li>
            <li>preprocessing.dot_reduction</li>
            <li>preprocessing.connect_lines</li>
        </preprocessing_queue>
        <use_anonymous value="true" />
    </other>
</config>

Python3 integer division

Try this:

a = 1
b = 2
int_div  = a // b

WPF: ItemsControl with scrollbar (ScrollViewer)

Put your ScrollViewer in a DockPanel and set the DockPanel MaxHeight property

[...]
<DockPanel MaxHeight="700">
  <ScrollViewer VerticalScrollBarVisibility="Auto">
   <ItemsControl ItemSource ="{Binding ...}">
     [...]
   </ItemsControl>
  </ScrollViewer>
</DockPanel>
[...]

How to read all of Inputstream in Server Socket JAVA

The problem you have is related to TCP streaming nature.

The fact that you sent 100 Bytes (for example) from the server doesn't mean you will read 100 Bytes in the client the first time you read. Maybe the bytes sent from the server arrive in several TCP segments to the client.

You need to implement a loop in which you read until the whole message was received. Let me provide an example with DataInputStream instead of BufferedinputStream. Something very simple to give you just an example.

Let's suppose you know beforehand the server is to send 100 Bytes of data.

In client you need to write:

byte[] messageByte = new byte[1000];
boolean end = false;
String dataString = "";

try 
{
    DataInputStream in = new DataInputStream(clientSocket.getInputStream());

    while(!end)
    {
        int bytesRead = in.read(messageByte);
        dataString += new String(messageByte, 0, bytesRead);
        if (dataString.length == 100)
        {
            end = true;
        }
    }
    System.out.println("MESSAGE: " + dataString);
}
catch (Exception e)
{
    e.printStackTrace();
}

Now, typically the data size sent by one node (the server here) is not known beforehand. Then you need to define your own small protocol for the communication between server and client (or any two nodes) communicating with TCP.

The most common and simple is to define TLV: Type, Length, Value. So you define that every message sent form server to client comes with:

  • 1 Byte indicating type (For example, it could also be 2 or whatever).
  • 1 Byte (or whatever) for length of message
  • N Bytes for the value (N is indicated in length).

So you know you have to receive a minimum of 2 Bytes and with the second Byte you know how many following Bytes you need to read.

This is just a suggestion of a possible protocol. You could also get rid of "Type".

So it would be something like:

byte[] messageByte = new byte[1000];
boolean end = false;
String dataString = "";

try 
{
    DataInputStream in = new DataInputStream(clientSocket.getInputStream());
    int bytesRead = 0;

    messageByte[0] = in.readByte();
    messageByte[1] = in.readByte();

    int bytesToRead = messageByte[1];

    while(!end)
    {
        bytesRead = in.read(messageByte);
        dataString += new String(messageByte, 0, bytesRead);
        if (dataString.length == bytesToRead )
        {
            end = true;
        }
    }
    System.out.println("MESSAGE: " + dataString);
}
catch (Exception e)
{
    e.printStackTrace();
}

The following code compiles and looks better. It assumes the first two bytes providing the length arrive in binary format, in network endianship (big endian). No focus on different encoding types for the rest of the message.

import java.nio.ByteBuffer;
import java.io.DataInputStream;
import java.net.ServerSocket;
import java.net.Socket;

class Test
{
    public static void main(String[] args)
    {
        byte[] messageByte = new byte[1000];
        boolean end = false;
        String dataString = "";

        try 
        {
            Socket clientSocket;
            ServerSocket server;

            server = new ServerSocket(30501, 100);
            clientSocket = server.accept();

            DataInputStream in = new DataInputStream(clientSocket.getInputStream());
            int bytesRead = 0;

            messageByte[0] = in.readByte();
            messageByte[1] = in.readByte();
            ByteBuffer byteBuffer = ByteBuffer.wrap(messageByte, 0, 2);

            int bytesToRead = byteBuffer.getShort();
            System.out.println("About to read " + bytesToRead + " octets");

            //The following code shows in detail how to read from a TCP socket

            while(!end)
            {
                bytesRead = in.read(messageByte);
                dataString += new String(messageByte, 0, bytesRead);
                if (dataString.length() == bytesToRead )
                {
                    end = true;
                }
            }

            //All the code in the loop can be replaced by these two lines
            //in.readFully(messageByte, 0, bytesToRead);
            //dataString = new String(messageByte, 0, bytesToRead);

            System.out.println("MESSAGE: " + dataString);
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }
}

Wildcard string comparison in Javascript

You should use RegExp (they are awesome) an easy solution is:

if( /^bird/.test(animals[i]) ){
    // a bird :D
}

Read the package name of an Android APK

For Windows following worked for me:

:: // Initializing variables
SET adb="C:\Users\<User name>\AppData\Local\Android\Sdk\platform-tools\adb"
SET aapt="C:\Users\<User name>\AppData\Local\Android\Sdk\build-tools\22.0.0\aapt"
SET APKPath=C:\Users\<User name>\Desktop\APK\Instant_Instal\

CD %APKPath%

:: // Searching for apk file and storing it
FOR /F "delims=" %%f IN ('dir /S /B *.apk') DO SET "APKFullPath=%%f"
SET apk=%APKFullPath%

:: // Command adb install apk, run apk
%adb% install %apk%

:: // Fetching package name from apk
%aapt% dump badging %APKFullPath% | FIND "package: name=" > temp.txt
FOR /F "tokens=2 delims='" %%s IN (temp.txt) DO SET pkgName=%%s
del temp.txt

:: // Launching apk
%adb% shell monkey -p %pkgName% -c android.intent.category.LAUNCHER 1

pause

Note

Please edit the paths of adb, aapt, APKPath according to the paths of adb, aapt, and the apk location in your system.

Working:

  • Here I have added the apk in a folder on Desktop "\Desktop\APK\Instant_Instal\".
  • The command %adb% install %apk% installs the application if the device is connected.
  • This %aapt% dump badging %APKFullPath% | FIND "package: name=" > temp.txt fetches package name and a few other details like version etc. of the apk and stores in a temp.txt file in same location as that of the apk.
  • FOR /F "tokens=2 delims='" %%s IN (temp.txt) DO SET pkgName=%%sextracts the package name and assigns topkgName` variable
  • Finally %adb% shell monkey -p %pkgName% -c android.intent.category.LAUNCHER 1 launches the app.

In essence the above code installs the apk from given location in desktop "Desktop\APK\Instant_Instal\" to the device and launches the application.

Generate C# class from XML

You can use xsd as suggested by Darin.

In addition to that it is recommended to edit the test.xsd-file to create a more reasonable schema.

type="xs:string" can be changed to type="xs:int" for integer values
minOccurs="0" can be changed to minOccurs="1" where the field is required
maxOccurs="unbounded" can be changed to maxOccurs="1" where only one item is allowed

You can create more advanced xsd-s if you want to validate your data further, but this will at least give you reasonable data types in the generated c#.

Why won't my PHP app send a 404 error?

If you want the server’s default error page to be displayed, you have to handle this in the server.

Receiver not registered exception error?

Lets assume your broadcastReceiver is defined like this:

private BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {

        // your code

    }
};

If you are using LocalBroadcast in an Activity, then this is how you'll unregister:

LocalBroadcastManager.getInstance(this).unregisterReceiver(broadcastReceiver);

If you are using LocalBroadcast in a Fragment, then this is how you'll unregister:

LocalBroadcastManager.getInstance(getActivity()).unregisterReceiver(broadcastReceiver);

If you are using normal broadcast in an Activity, then this is how you'll unregister:

unregisterReceiver(broadcastReceiver);

If you are using normal broadcast in a Fragment, then this is how you'll unregister:

getActivity().unregisterReceiver(broadcastReceiver);

How to re-render flatlist?

I am using functional component, in that I am using Flatlist with redux data. I am managing all the state with Redux store. Here is the solution to update the Flatlist data after the api call.

I was first doing like this:-

const DATA  = useSelector((state) => state.address.address);


<FlatList
    style = {styles.myAddressList}
    data = {DATA}
    renderItem = {renderItem}
    keyExtractor = {item => item._id}
    ListEmptyComponent = {EmptyList}
    ItemSeparatorComponent={SeparatorWhite}
    extraData = {refresh}
    
    />

but the data was not re-rendering my Flatlist data at all.

As a solution I did like given Below:-

<FlatList
    style = {styles.myAddressList}
    data = {useSelector((state) => state.address.address)}
    renderItem = {renderItem}
    keyExtractor = {item => item._id}
    ListEmptyComponent = {EmptyList}
    ItemSeparatorComponent={SeparatorWhite}
    />

I am passing the Redux state directly to the Flatlist Datasource rather than allocating it to the variable.

Thank you.

Send inline image in email

I added the complete code below to display images in Gmail,Thunderbird and other email clients :

MailMessage mailWithImg = getMailWithImg();
MySMTPClient.Send(mailWithImg); //* Set up your SMTPClient before!

private MailMessage getMailWithImg()
{
    MailMessage mail = new MailMessage();
    mail.IsBodyHtml = true;
    mail.AlternateViews.Add(getEmbeddedImage("c:/image.png"));
    mail.From = new MailAddress("yourAddress@yourDomain");
    mail.To.Add("recipient@hisDomain");
    mail.Subject = "yourSubject";
    return mail;
}
private AlternateView getEmbeddedImage(String filePath)
 {
    // below line was corrected to include the mediatype so it displays in all 
    // mail clients. previous solution only displays in Gmail the inline images 
    LinkedResource res = new LinkedResource(filePath, MediaTypeNames.Image.Jpeg);  
    res.ContentId = Guid.NewGuid().ToString();
    string htmlBody = @"<img src='cid:" + res.ContentId + @"'/>";
    AlternateView alternateView = AlternateView.CreateAlternateViewFromString(htmlBody,  
     null, MediaTypeNames.Text.Html);
    alternateView.LinkedResources.Add(res);
    return alternateView;
}

Check if string is upper, lower, or mixed case in Python

I want to give a shoutout for using re module for this. Specially in the case of case sensitivity.

We use the option re.IGNORECASE while compiling the regex for use of in production environments with large amounts of data.

>>> import re
>>> m = ['isalnum','isalpha', 'isdigit', 'islower', 'isspace', 'istitle', 'isupper', 'ISALNUM', 'ISALPHA', 'ISDIGIT', 'ISLOWER', 'ISSPACE', 'ISTITLE', 'ISUPPER']
>>>
>>>
>>> pattern = re.compile('is')
>>>
>>> [word for word in m if pattern.match(word)]
['isalnum', 'isalpha', 'isdigit', 'islower', 'isspace', 'istitle', 'isupper']

However try to always use the in operator for string comparison as detailed in this post

faster-operation-re-match-or-str

Also detailed in the one of the best books to start learning python with

idiomatic-python

Sum a list of numbers in Python

You can try this way:

a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
sm = sum(a[0:len(a)]) # Sum of 'a' from 0 index to 9 index. sum(a) == sum(a[0:len(a)]
print(sm) # Python 3
print sm  # Python 2

How to show/hide an element on checkbox checked/unchecked states using jQuery?

Try this

<script>
    $().ready(function(){
        $('.coupon_question').live('click',function() 
        {
            if ($('.coupon_question').is(':checked')) {
                $(".answer").show();
            } else {
                $(".answer").hide();
            } 
        });
    });
</script>

Can I install Python 3.x and 2.x on the same Windows computer?

I think there is an option to setup the windows file association for .py files in the installer. Uncheck it and you should be fine.

If not, you can easily re-associate .py files with the previous version. The simplest way is to right click on a .py file, select "open with" / "choose program". On the dialog that appears, select or browse to the version of python you want to use by default, and check the "always use this program to open this kind of file" checkbox.

JavaScript: replace last occurrence of text in a string

A simple answer without any regex would be:

str = str.substr(0, str.lastIndexOf(list[i])) + 'finish'

Replace CRLF using powershell

Adding another version based on example above by @ricky89 and @mklement0 with few improvements:

Script to process:

  • *.txt files in the current folder
  • replace LF with CRLF (Unix to Windows line-endings)
  • save resulting files to CR-to-CRLF subfolder
  • tested on 100MB+ files, PS v5;

LF-to-CRLF.ps1:

# get current dir
$currentDirectory = Split-Path $MyInvocation.MyCommand.Path -Parent

# create subdir CR-to-CRLF for new files
$outDir = $(Join-Path $currentDirectory "CR-to-CRLF")
New-Item -ItemType Directory -Force -Path $outDir | Out-Null

# get all .txt files
Get-ChildItem $currentDirectory -Force | Where-Object {$_.extension -eq ".txt"} | ForEach-Object {
  $file = New-Object System.IO.StreamReader -Arg $_.FullName
  # Resulting file will be in CR-to-CRLF subdir
  $outstream = [System.IO.StreamWriter] $(Join-Path  $outDir $($_.BaseName + $_.Extension))
  $count = 0 
  # read line by line, replace CR with CRLF in each by saving it with $outstream.WriteLine
  while ($line = $file.ReadLine()) {
        $count += 1
        $outstream.WriteLine($line)
    }
  $file.close()
  $outstream.close()
  Write-Host ("$_`: " + $count + ' lines processed.')
}

Cannot read property 'style' of undefined -- Uncaught Type Error

Add your <script> to the bottom of your <body>, or add an event listener for DOMContentLoaded following this StackOverflow question.

If that script executes in the <head> section of the code, document.getElementsByClassName(...) will return an empty array because the DOM is not loaded yet.

You're getting the Type Error because you're referencing search_span[0], but search_span[0] is undefined.

This works when you execute it in Dev Tools because the DOM is already loaded.

What are the -Xms and -Xmx parameters when starting JVM?

The question itself has already been addressed above. Just adding part of the default values.

As per http://docs.oracle.com/cd/E13150_01/jrockit_jvm/jrockit/jrdocs/refman/optionX.html

The default value of Xmx will depend on platform and amount of memory available in the system.

How to make function decorators and chain them together?

Alternatively, you could write a factory function which return a decorator which wraps the return value of the decorated function in a tag passed to the factory function. For example:

from functools import wraps

def wrap_in_tag(tag):
    def factory(func):
        @wraps(func)
        def decorator():
            return '<%(tag)s>%(rv)s</%(tag)s>' % (
                {'tag': tag, 'rv': func()})
        return decorator
    return factory

This enables you to write:

@wrap_in_tag('b')
@wrap_in_tag('i')
def say():
    return 'hello'

or

makebold = wrap_in_tag('b')
makeitalic = wrap_in_tag('i')

@makebold
@makeitalic
def say():
    return 'hello'

Personally I would have written the decorator somewhat differently:

from functools import wraps

def wrap_in_tag(tag):
    def factory(func):
        @wraps(func)
        def decorator(val):
            return func('<%(tag)s>%(val)s</%(tag)s>' %
                        {'tag': tag, 'val': val})
        return decorator
    return factory

which would yield:

@wrap_in_tag('b')
@wrap_in_tag('i')
def say(val):
    return val
say('hello')

Don't forget the construction for which decorator syntax is a shorthand:

say = wrap_in_tag('b')(wrap_in_tag('i')(say)))

Check if table exists

I don't actually find any of the presented solutions here to be fully complete so I'll add my own. Nothing new here. You can stitch this together from the other presented solutions plus various comments.

There are at least two things you'll have to make sure:

  1. Make sure you pass the table name to the getTables() method, rather than passing a null value. In the first case you let the database server filter the result for you, in the second you request a list of all tables from the server and then filter the list locally. The former is much faster if you are only searching for a single table.

  2. Make sure to check the table name from the resultset with an equals match. The reason is that the getTables() does pattern matching on the query for the table and the _ character is a wildcard in SQL. Suppose you are checking for the existence of a table named EMPLOYEE_SALARY. You'll then get a match on EMPLOYEESSALARY too which is not what you want.

Ohh, and do remember to close those resultsets. Since Java 7 you would want to use a try-with-resources statement for that.

Here's a complete solution:

public static boolean tableExist(Connection conn, String tableName) throws SQLException {
    boolean tExists = false;
    try (ResultSet rs = conn.getMetaData().getTables(null, null, tableName, null)) {
        while (rs.next()) { 
            String tName = rs.getString("TABLE_NAME");
            if (tName != null && tName.equals(tableName)) {
                tExists = true;
                break;
            }
        }
    }
    return tExists;
}

You may want to consider what you pass as the types parameter (4th parameter) on your getTables() call. Normally I would just leave at null because you don't want to restrict yourself. A VIEW is as good as a TABLE, right? These days many databases allow you to update through a VIEW so restricting yourself to only TABLE type is in most cases not the way to go. YMMV.

What's wrong with foreign keys?

"They can make deleting records more cumbersome - you can't delete the "master" record where there are records in other tables where foreign keys would violate that constraint."

It's important to remember that the SQL standard defines actions that are taken when a foreign key is deleted or updated. The ones I know of are:

  • ON DELETE RESTRICT - Prevents any rows in the other table that have keys in this column from being deleted. This is what Ken Ray described above.
  • ON DELETE CASCADE - If a row in the other table is deleted, delete any rows in this table that reference it.
  • ON DELETE SET DEFAULT - If a row in the other table is deleted, set any foreign keys referencing it to the column's default.
  • ON DELETE SET NULL - If a row in the other table is deleted, set any foreign keys referencing it in this table to null.
  • ON DELETE NO ACTION - This foreign key only marks that it is a foreign key; namely for use in OR mappers.

These same actions also apply to ON UPDATE.

The default seems to depend on which server you're using.

C# create simple xml file

I'd recommend serialization,

public class Person
{
      public  string FirstName;
      public  string MI;
      public  string LastName;
}

static void Serialize()
{
      clsPerson p = new Person();
      p.FirstName = "Jeff";
      p.MI = "A";
      p.LastName = "Price";
      System.Xml.Serialization.XmlSerializer x = new System.Xml.Serialization.XmlSerializer(p.GetType());
      x.Serialize(System.Console.Out, p);
      System.Console.WriteLine();
      System.Console.WriteLine(" --- Press any key to continue --- ");
      System.Console.ReadKey();
}

You can further control serialization with attributes.
But if it is simple, you could use XmlDocument:

using System;
using System.Xml;

public class GenerateXml {
    private static void Main() {
        XmlDocument doc = new XmlDocument();
        XmlNode docNode = doc.CreateXmlDeclaration("1.0", "UTF-8", null);
        doc.AppendChild(docNode);

        XmlNode productsNode = doc.CreateElement("products");
        doc.AppendChild(productsNode);

        XmlNode productNode = doc.CreateElement("product");
        XmlAttribute productAttribute = doc.CreateAttribute("id");
        productAttribute.Value = "01";
        productNode.Attributes.Append(productAttribute);
        productsNode.AppendChild(productNode);

        XmlNode nameNode = doc.CreateElement("Name");
        nameNode.AppendChild(doc.CreateTextNode("Java"));
        productNode.AppendChild(nameNode);
        XmlNode priceNode = doc.CreateElement("Price");
        priceNode.AppendChild(doc.CreateTextNode("Free"));
        productNode.AppendChild(priceNode);

        // Create and add another product node.
        productNode = doc.CreateElement("product");
        productAttribute = doc.CreateAttribute("id");
        productAttribute.Value = "02";
        productNode.Attributes.Append(productAttribute);
        productsNode.AppendChild(productNode);
        nameNode = doc.CreateElement("Name");
        nameNode.AppendChild(doc.CreateTextNode("C#"));
        productNode.AppendChild(nameNode);
        priceNode = doc.CreateElement("Price");
        priceNode.AppendChild(doc.CreateTextNode("Free"));
        productNode.AppendChild(priceNode);

        doc.Save(Console.Out);
    }
}

And if it needs to be fast, use XmlWriter:

public static void WriteXML()
{
    // Create an XmlWriterSettings object with the correct options.
    System.Xml.XmlWriterSettings settings = new System.Xml.XmlWriterSettings();
    settings.Indent = true;
    settings.IndentChars = "    "; //  "\t";
    settings.OmitXmlDeclaration = false;
    settings.Encoding = System.Text.Encoding.UTF8;

    using (System.Xml.XmlWriter writer = System.Xml.XmlWriter.Create("data.xml", settings))
    {

        writer.WriteStartDocument();
        writer.WriteStartElement("books");

        for (int i = 0; i < 100; ++i)
        {
            writer.WriteStartElement("book");
            writer.WriteElementString("item", "Book "+ (i+1).ToString());
            writer.WriteEndElement();
        }

        writer.WriteEndElement();

        writer.Flush();
        writer.Close();
    } // End Using writer 

}

And btw, the fastest way to read XML is XmlReader:

public static void ReadXML()
{
    using (System.Xml.XmlReader xmlReader = System.Xml.XmlReader.Create("http://www.ecb.int/stats/eurofxref/eurofxref-daily.xml"))
    {
        while (xmlReader.Read())
        {
            if ((xmlReader.NodeType == System.Xml.XmlNodeType.Element) && (xmlReader.Name == "Cube"))
            {
                if (xmlReader.HasAttributes)
                    System.Console.WriteLine(xmlReader.GetAttribute("currency") + ": " + xmlReader.GetAttribute("rate"));
            }

        } // Whend 

    } // End Using xmlReader

    System.Console.ReadKey();
}

And the most convenient way to read XML is to just deserialize the XML into a class.
This also works for creating the serialization classes, btw.
You can generate the class from XML with Xml2CSharp:
https://xmltocsharp.azurewebsites.net/

Setting Java heap space under Maven 2 on Windows

If you are running out of heap space during the surefire (or failsafe) JUnit testing run, changing MAVEN_OPTS may not help you. I kept trying different configurations in MAVEN_OPTS with no luck until I found this post that fixed the problem.

Basically the JUnits fork off into their own environment and ignore the settings in MAVEN_OPTS. You need to configure surefire in your pom to add more memory for the JUnits.

Hopefully this can save someone else some time!


Edit: Copying solution from Keith Chapman's blog just in case the link breaks some day:

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-surefire-plugin</artifactId>
  <configuration>
    <forkMode>pertest</forkMode> 
    <argLine>-Xms256m -Xmx512m</argLine>
    <testFailureIgnore>false</testFailureIgnore> 
    <skip>false</skip> 
    <includes> 
      <include>**/*IntegrationTestSuite.java</include>
    </includes>
  </configuration>
</plugin>

Update (5/31/2017): Thanks to @johnstosh for pointing this out - surefire has evolved a bit since I put this answer out there. Here is a link to their documentation and an updated code sample (arg line is still the important part for this question):

  <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <version>2.20</version>
    <configuration>
        <forkCount>3</forkCount>
        <reuseForks>true</reuseForks>
        <argLine>-Xmx1024m -XX:MaxPermSize=256m</argLine>
        <systemPropertyVariables>
            <databaseSchema>MY_TEST_SCHEMA_${surefire.forkNumber}</databaseSchema>
        </systemPropertyVariables>
        <workingDirectory>FORK_DIRECTORY_${surefire.forkNumber}</workingDirectory>
    </configuration>
  </plugin>

Moving Average Pandas

A moving average can also be calculated and visualized directly in a line chart by using the following code:

Example using stock price data:

import pandas_datareader.data as web
import matplotlib.pyplot as plt
import datetime
plt.style.use('ggplot')

# Input variables
start = datetime.datetime(2016, 1, 01)
end = datetime.datetime(2018, 3, 29)
stock = 'WFC'

# Extrating data
df = web.DataReader(stock,'morningstar', start, end)
df = df['Close']

print df 

plt.plot(df['WFC'],label= 'Close')
plt.plot(df['WFC'].rolling(9).mean(),label= 'MA 9 days')
plt.plot(df['WFC'].rolling(21).mean(),label= 'MA 21 days')
plt.legend(loc='best')
plt.title('Wells Fargo\nClose and Moving Averages')
plt.show()

Tutorial on how to do this: https://youtu.be/XWAPpyF62Vg

Find the item with maximum occurrences in a list

In your question, you asked for the fastest way to do it. As has been demonstrated repeatedly, particularly with Python, intuition is not a reliable guide: you need to measure.

Here's a simple test of several different implementations:

import sys
from collections import Counter, defaultdict
from itertools import groupby
from operator import itemgetter
from timeit import timeit

L = [1,2,45,55,5,4,4,4,4,4,4,5456,56,6,7,67]

def max_occurrences_1a(seq=L):
    "dict iteritems"
    c = dict()
    for item in seq:
        c[item] = c.get(item, 0) + 1
    return max(c.iteritems(), key=itemgetter(1))

def max_occurrences_1b(seq=L):
    "dict items"
    c = dict()
    for item in seq:
        c[item] = c.get(item, 0) + 1
    return max(c.items(), key=itemgetter(1))

def max_occurrences_2(seq=L):
    "defaultdict iteritems"
    c = defaultdict(int)
    for item in seq:
        c[item] += 1
    return max(c.iteritems(), key=itemgetter(1))

def max_occurrences_3a(seq=L):
    "sort groupby generator expression"
    return max(((k, sum(1 for i in g)) for k, g in groupby(sorted(seq))), key=itemgetter(1))

def max_occurrences_3b(seq=L):
    "sort groupby list comprehension"
    return max([(k, sum(1 for i in g)) for k, g in groupby(sorted(seq))], key=itemgetter(1))

def max_occurrences_4(seq=L):
    "counter"
    return Counter(L).most_common(1)[0]

versions = [max_occurrences_1a, max_occurrences_1b, max_occurrences_2, max_occurrences_3a, max_occurrences_3b, max_occurrences_4]

print sys.version, "\n"

for vers in versions:
    print vers.__doc__, vers(), timeit(vers, number=20000)

The results on my machine:

2.7.2 (v2.7.2:8527427914a2, Jun 11 2011, 15:22:34) 
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] 

dict iteritems (4, 6) 0.202214956284
dict items (4, 6) 0.208412885666
defaultdict iteritems (4, 6) 0.221301078796
sort groupby generator expression (4, 6) 0.383440971375
sort groupby list comprehension (4, 6) 0.402786016464
counter (4, 6) 0.564319133759

So it appears that the Counter solution is not the fastest. And, in this case at least, groupby is faster. defaultdict is good but you pay a little bit for its convenience; it's slightly faster to use a regular dict with a get.

What happens if the list is much bigger? Adding L *= 10000 to the test above and reducing the repeat count to 200:

dict iteritems (4, 60000) 10.3451900482
dict items (4, 60000) 10.2988479137
defaultdict iteritems (4, 60000) 5.52838587761
sort groupby generator expression (4, 60000) 11.9538850784
sort groupby list comprehension (4, 60000) 12.1327362061
counter (4, 60000) 14.7495789528

Now defaultdict is the clear winner. So perhaps the cost of the 'get' method and the loss of the inplace add adds up (an examination of the generated code is left as an exercise).

But with the modified test data, the number of unique item values did not change so presumably dict and defaultdict have an advantage there over the other implementations. So what happens if we use the bigger list but substantially increase the number of unique items? Replacing the initialization of L with:

LL = [1,2,45,55,5,4,4,4,4,4,4,5456,56,6,7,67]
L = []
for i in xrange(1,10001):
    L.extend(l * i for l in LL)

dict iteritems (2520, 13) 17.9935798645
dict items (2520, 13) 21.8974409103
defaultdict iteritems (2520, 13) 16.8289561272
sort groupby generator expression (2520, 13) 33.853593111
sort groupby list comprehension (2520, 13) 36.1303369999
counter (2520, 13) 22.626899004

So now Counter is clearly faster than the groupby solutions but still slower than the iteritems versions of dict and defaultdict.

The point of these examples isn't to produce an optimal solution. The point is that there often isn't one optimal general solution. Plus there are other performance criteria. The memory requirements will differ substantially among the solutions and, as the size of the input goes up, memory requirements may become the overriding factor in algorithm selection.

Bottom line: it all depends and you need to measure.

Angular 2 - Setting selected value on dropdown list

In my case i was returning string value from my api eg: "35" and in my HTML i was using

       <mat-select placeholder="State*" formControlName="states" [(ngModel)]="selectedState" (ngModelChange)="getDistricts()">
            <mat-option *ngFor="let state of formInputs.states" [value]="state.stateId">
              {{ state.stateName }}
            </mat-option>
          </mat-select>

Like others mentioned in the comment value will only accept integer values i guess. So what I did is I converted my string value to integer in my component class like below

          var x = user.state;
          var y: number = +x;

and then assigned it like

  this.EditProfileForm.get('states').setValue(y);

Now the correct values is getting setting by default.

How to terminate a python subprocess launched with shell=True

what i feel like we could use:

import os
import signal
import subprocess
p = subprocess.Popen(cmd, stdout=subprocess.PIPE, shell=True)

os.killpg(os.getpgid(pro.pid), signal.SIGINT)

this will not kill all your task but the process with the p.pid

How to identify which columns are not "NA" per row in a matrix?

Try:

which( !is.na(p), arr.ind=TRUE)

Which I think is just as informative and probably more useful than the output you specified, But if you really wanted the list version, then this could be used:

> apply(p, 1, function(x) which(!is.na(x)) )
[[1]]
[1] 2 3

[[2]]
[1] 4 7

[[3]]
integer(0)

[[4]]
[1] 5

[[5]]
integer(0)

Or even with smushing together with paste:

lapply(apply(p, 1, function(x) which(!is.na(x)) ) , paste, collapse=", ")

The output from which function the suggested method delivers the row and column of non-zero (TRUE) locations of logical tests:

> which( !is.na(p), arr.ind=TRUE)
     row col
[1,]   1   2
[2,]   1   3
[3,]   2   4
[4,]   4   5
[5,]   2   7

Without the arr.ind parameter set to non-default TRUE, you only get the "vector location" determined using the column major ordering the R has as its convention. R-matrices are just "folded vectors".

> which( !is.na(p) )
[1]  6 11 17 24 32

Making a WinForms TextBox behave like your browser's address bar

My Solution is pretty primitive but works fine for my purpose

private async void TextBox_GotFocus(object sender, RoutedEventArgs e)
{
    if (sender is TextBox)
    {
        await Task.Delay(100);
        (sender as TextBox).SelectAll();
    }
}

Illegal character in path at index 16

Did you try this?

new File("<PATH OF YOUR FILE>").toURI().toString();

jQuery DataTable overflow and text-wrapping issues

I'm way late here, but after reading @Greg Pettit's answer and a couple of blogs or other SO questions I unfortunately can't remember I decided to just make a couple of dataTables plugins to deal with this.

I put them on bitbucket in a Mercurial repo. I follwed the fnSetFilteringDelay plugin and just changed the comments and code inside, as I've never made a plugin for anything before. I made 2, and feel free to use them, contribute to them, or provide suggestions.

  • dataTables.TruncateCells - truncates each cell in a column down to a set number of characters, replacing the last 3 with an ellipses, and puts the full pre-truncated text in the cell's title attributed.

  • dataTables.BreakCellText - attempts to insert a break character every X, user defined, characters in each cell in the column. There are quirks regarding cells that contain both spaces and hyphens, you can get some weird looking results (like a couple of characters straggling after the last inserted
    character). Maybe someone can make that more robust, or you can just fiddle with the breakPos for the column to make it look alright with your data.

SQL how to check that two tables has exactly the same data?

To compare T1(PK, A, B) and T2(PK, A, B).

First compare primary key sets to look for missing key values on either side:

SELECT T1.*, T2.* FROM T1 FULL OUTER JOIN T2 ON T1.PK=T2.PK WHERE T1.PK IS NULL OR T2.PK IS NULL;

Then list all value mismatch:

SELECT T1.PK, 'A' AS columnName, T1.A AS leftValue, T2.A AS rightValue FROM T1 JOIN T2 ON T1.PK=T2.PK WHERE COALESCE(T1.A,0) != COALESCE(T2.A,0)
UNION ALL
SELECT T1.PK, 'B' AS columnName, T1.B AS leftValue, T2.B AS rightValue FROM T1 JOIN T2 ON T1.PK=T2.PK WHERE COALESCE(T1.B,0) != COALESCE(T2.B,0)

A and B must be of same type. You can use INFORMATION SCHEMA to generate the SELECT. Don't forget the COALESCE to also include IS NULL results. You could also use FULL OUTER JOIN and COALESCE(T1.PK,0)=COALESCE(T2.PK,0).

For example for columns of type varchar:

SELECT concat('SELECT T1.PK, ''', COLUMN_NAME, ''' AS columnName, T1.', COLUMN_NAME, ' AS leftValue, T2.', COLUMN_NAME, ' AS rightValue FROM T1 JOIN T2 ON T1.PK=T2.PK WHERE COALESCE(T1.',COLUMN_NAME, ',0)!=COALESCE(T2.', COLUMN_NAME, ',0)')
FROM INFORMATION_SCHEMA.COLUMNS 
WHERE TABLE_NAME='T1' AND DATA_TYPE IN ('nvarchar','varchar');

Manifest Merger failed with multiple errors in Android Studio

The minium sdk version should be same as of the modules/lib you are using For example: Your module min sdk version is 26 and your app min sdk version is 21 It should be same.

Bootstrap Modal sitting behind backdrop

if we cannot delete backdrop and/or we have component framework such angular or vue we cannot move modal to the root. i did this trick: put my custom modal-backdrop container(with aditional class) as sibling for modal-dialog container and added some css

<div bsModal #moneyModal="bs-modal" class="modal fade" tabindex="-1" role="dialog">
    <!-- magic container-->
    <div class="modal-holder modal-backdrop" (click)="moneyModal.hide()"></div>
    <div class="modal-dialog modal-sm" role="document">
        <div class="modal-content">
            <div class="modal-body">
                ....
            </div>
        </div>
    </div>
</div>

and css

.modal-backdrop{z-index: -1}// or you can disable modal-backdrop
.modal-holder.modal-backdrop{z-index: 100}
.modal-holder + .modal-dialog {z-index: 1000}

Image Greyscale with CSS & re-color on mouse-over?

Answered here: Convert an image to grayscale in HTML/CSS

You don't even need to use two images which sounds like a pain or an image manipulation library, you can do it with cross browser support (current versions) and just use CSS. This is a progressive enhancement approach which just falls back to color versions on older browsers:

img {
  filter: url(filters.svg#grayscale);
  /* Firefox 3.5+ */
  filter: gray;
  /* IE6-9 */
  -webkit-filter: grayscale(1);
  /* Google Chrome & Safari 6+ */
}
img:hover {
  filter: none;
  -webkit-filter: none;
}

and filters.svg file like this:

<svg xmlns="http://www.w3.org/2000/svg">
  <filter id="grayscale">
    <feColorMatrix type="matrix" values="0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0 0 0 1 0" />
  </filter>
</svg>

How to get values from selected row in DataGrid for Windows Form Application?

Description

Assuming i understand your question.

You can get the selected row using the DataGridView.SelectedRows Collection. If your DataGridView allows only one selected, have a look at my sample.

DataGridView.SelectedRows Gets the collection of rows selected by the user.

Sample

if (dataGridView1.SelectedRows.Count != 0)
{
    DataGridViewRow row = this.dataGridView1.SelectedRows[0];
    row.Cells["ColumnName"].Value
}

More Information

Blur or dim background when Android PopupWindow active

ok, so i follow uhmdown's answer for dimming background activity when pop window is open. But it creates problem for me. it was dimming activity and include popup window (means dimmed-black layered on both activity and popup also, it can not be separate them).

so i tried this way,

create an dimming_black.xml file for dimming effect,

 <?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <solid android:color="#33000000" />
</shape>

And add as background in FrameLayout as root xml tag, also put my other controls in LinearLayout like this layout.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:background="@drawable/ff_drawable_black">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:layout_gravity="bottom"
        android:background="@color/white">

        // other codes...
    </LinearLayout>

</FrameLayout>

at last i show popup on my MainActivity with some extra parameter set as below.

           //instantiate popup window
            popupWindow = new PopupWindow(viewPopup, LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT, true);

            //display the popup window
            popupWindow.showAtLocation(layout_ff, Gravity.BOTTOM, 0, 0);

Result: enter image description here

it works for me, also solved problem as commented by BaDo. With this Actionbar also can be dimmed.

P.s i am not saying uhmdown's is wrong. i learnt form his answer and try to evolve for my problem. I also confused whether this is a good way or not.

Any suggestions is also appreciated also sorry for my bad English.

How to pass parameters in $ajax POST?

I would recommend you to make use of the $.post or $.get syntax of jQuery for simple cases:

$.post('superman', { field1: "hello", field2 : "hello2"}, 
    function(returnedData){
         console.log(returnedData);
});

If you need to catch the fail cases, just do this:

$.post('superman', { field1: "hello", field2 : "hello2"}, 
    function(returnedData){
         console.log(returnedData);
}).fail(function(){
      console.log("error");
});

Additionally, if you always send a JSON string, you can use $.getJSON or $.post with one more parameter at the very end.

$.post('superman', { field1: "hello", field2 : "hello2"}, 
     function(returnedData){
        console.log(returnedData);
}, 'json');

Get array of object's keys

You can use jQuery's $.map.

var foo = { 'alpha' : 'puffin', 'beta' : 'beagle' },
keys = $.map(foo, function(v, i){
  return i;
});

The type or namespace cannot be found (are you missing a using directive or an assembly reference?)

This error comes because compile does not know where to find the class..so it occurs mainly when u copy or import item ..to solve this .. 1.change the namespace in the formname.cs and formname.designer.cs to the name of your project .

PHP DOMDocument loadHTML not encoding UTF-8 correctly

I am using php 7.3.8 on a manjaro and I was working with Persian content. This solved my problem:

$html = 'hi</b><p>????<div>?????9 ?';
$doc = new DOMDocument('1.0', 'UTF-8');
$doc->loadHTML(mb_convert_encoding($html, 'HTML-ENTITIES', 'UTF-8'));
print $doc->saveHTML($doc->documentElement) . PHP_EOL . PHP_EOL;

insert/delete/update trigger in SQL server

I use that for all status (update, insert and delete)

CREATE TRIGGER trg_Insert_Test
ON [dbo].[MyTable]
AFTER UPDATE, INSERT, DELETE 
AS
BEGIN
SET NOCOUNT ON;

DECLARE @Activity  NVARCHAR (50)

-- update
IF EXISTS (SELECT * FROM inserted) AND EXISTS (SELECT * FROM deleted)
BEGIN
    SET @Activity = 'UPDATE'
END

-- insert
IF EXISTS (SELECT * FROM inserted) AND NOT EXISTS(SELECT * FROM deleted)
BEGIN
    SET @Activity = 'INSERT'
END

-- delete
IF EXISTS (SELECT * FROM deleted) AND NOT EXISTS(SELECT * FROM inserted)
BEGIN
    SET @Activity = 'DELETE'
END



-- delete temp table
IF OBJECT_ID('tempdb..#tmpTbl') IS NOT NULL DROP TABLE #tmpTbl

-- get last 1 row
SELECT * INTO #tmpTbl FROM (SELECT TOP 1 * FROM (SELECT * FROM inserted
                                                 UNION 
                                                 SELECT * FROM deleted
                                                 ) AS A ORDER BY A.Date DESC
                            ) AS T


-- try catch
BEGIN TRY 

    INSERT INTO MyTable  (
           [Code]
          ,[Name]
           .....
          ,[Activity])
    SELECT [Code]
          ,[Name]
          ,@Activity 
    FROM #tmpTbl

END TRY BEGIN CATCH END CATCH


-- delete temp table
IF OBJECT_ID('tempdb..#tmpTbl') IS NOT NULL DROP TABLE #tmpTbl

SET NOCOUNT OFF;
END

Entity Framework - Linq query with order by and group by

You can try to cast the result of GroupBy and Take into an Enumerable first then process the rest (building on the solution provided by NinjaNye

var groupByReference = (from m in context.Measurements
                              .GroupBy(m => m.Reference)
                              .Take(numOfEntries).AsEnumerable()
                               .Select(g => new {Creation = g.FirstOrDefault().CreationTime, 
                                             Avg = g.Average(m => m.CreationTime.Ticks),
                                                Items = g })
                              .OrderBy(x => x.Creation)
                              .ThenBy(x => x.Avg)
                              .ToList() select m);

Your sql query would look similar (depending on your input) this

SELECT TOP (3) [t1].[Reference] AS [Key]
FROM (
    SELECT [t0].[Reference]
    FROM [Measurements] AS [t0]
    GROUP BY [t0].[Reference]
    ) AS [t1]
GO

-- Region Parameters
DECLARE @x1 NVarChar(1000) = 'Ref1'
-- EndRegion
SELECT [t0].[CreationTime], [t0].[Id], [t0].[Reference]
FROM [Measurements] AS [t0]
WHERE @x1 = [t0].[Reference]
GO

-- Region Parameters
DECLARE @x1 NVarChar(1000) = 'Ref2'
-- EndRegion
SELECT [t0].[CreationTime], [t0].[Id], [t0].[Reference]
FROM [Measurements] AS [t0]
WHERE @x1 = [t0].[Reference]

Installed Ruby 1.9.3 with RVM but command line doesn't show ruby -v

  • Open Terminal.
  • Go to Edit -> Profile Preferences.
  • Select the Title & command Tab in the window opened.
  • Mark the checkbox Run command as login shell.
  • close the window and restart the Terminal.

Check this Official Linkenter image description here

Load HTML File Contents to Div [without the use of iframes]

2019
Using fetch

<script>
fetch('page.html')
  .then(data => data.text())
  .then(html => document.getElementById('elementID').innerHTML = html);
</script>

<div id='elementID'> </div>

fetch needs to receive a http or https link, this means that it won't work locally.

Note: As Altimus Prime said, it is a feature for modern browsers

Platform.runLater and Task in JavaFX

Use Platform.runLater(...) for quick and simple operations and Task for complex and big operations .

Example: Why Can't we use Platform.runLater(...) for long calculations (Taken from below reference).

Problem: Background thread which just counts from 0 to 1 million and update progress bar in UI.

Code using Platform.runLater(...):

final ProgressBar bar = new ProgressBar();
new Thread(new Runnable() {
    @Override public void run() {
    for (int i = 1; i <= 1000000; i++) {
        final int counter = i;
        Platform.runLater(new Runnable() {
            @Override public void run() {
                bar.setProgress(counter / 1000000.0);
            }
        });
    }
}).start();

This is a hideous hunk of code, a crime against nature (and programming in general). First, you’ll lose brain cells just looking at this double nesting of Runnables. Second, it is going to swamp the event queue with little Runnables — a million of them in fact. Clearly, we needed some API to make it easier to write background workers which then communicate back with the UI.

Code using Task :

Task task = new Task<Void>() {
    @Override public Void call() {
        static final int max = 1000000;
        for (int i = 1; i <= max; i++) {
            updateProgress(i, max);
        }
        return null;
    }
};

ProgressBar bar = new ProgressBar();
bar.progressProperty().bind(task.progressProperty());
new Thread(task).start();

it suffers from none of the flaws exhibited in the previous code

Reference : Worker Threading in JavaFX 2.0

How to handle button clicks using the XML onClick within Fragments

ButterKnife is probably the best solution for the clutter problem. It uses annotation processors to generate the so called "old method" boilerplate code.

But the onClick method can still be used, with a custom inflator.

How to use

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup cnt, Bundle state) {
    inflater = FragmentInflatorFactory.inflatorFor(inflater, this);
    return inflater.inflate(R.layout.fragment_main, cnt, false);
}

Implementation

public class FragmentInflatorFactory implements LayoutInflater.Factory {

    private static final int[] sWantedAttrs = { android.R.attr.onClick };

    private static final Method sOnCreateViewMethod;
    static {
        // We could duplicate its functionallity.. or just ignore its a protected method.
        try {
            Method method = LayoutInflater.class.getDeclaredMethod(
                    "onCreateView", String.class, AttributeSet.class);
            method.setAccessible(true);
            sOnCreateViewMethod = method;
        } catch (NoSuchMethodException e) {
            // Public API: Should not happen.
            throw new RuntimeException(e);
        }
    }

    private final LayoutInflater mInflator;
    private final Object mFragment;

    public FragmentInflatorFactory(LayoutInflater delegate, Object fragment) {
        if (delegate == null || fragment == null) {
            throw new NullPointerException();
        }
        mInflator = delegate;
        mFragment = fragment;
    }

    public static LayoutInflater inflatorFor(LayoutInflater original, Object fragment) {
        LayoutInflater inflator = original.cloneInContext(original.getContext());
        FragmentInflatorFactory factory = new FragmentInflatorFactory(inflator, fragment);
        inflator.setFactory(factory);
        return inflator;
    }

    @Override
    public View onCreateView(String name, Context context, AttributeSet attrs) {
        if ("fragment".equals(name)) {
            // Let the Activity ("private factory") handle it
            return null;
        }

        View view = null;

        if (name.indexOf('.') == -1) {
            try {
                view = (View) sOnCreateViewMethod.invoke(mInflator, name, attrs);
            } catch (IllegalAccessException e) {
                throw new AssertionError(e);
            } catch (InvocationTargetException e) {
                if (e.getCause() instanceof ClassNotFoundException) {
                    return null;
                }
                throw new RuntimeException(e);
            }
        } else {
            try {
                view = mInflator.createView(name, null, attrs);
            } catch (ClassNotFoundException e) {
                return null;
            }
        }

        TypedArray a = context.obtainStyledAttributes(attrs, sWantedAttrs);
        String methodName = a.getString(0);
        a.recycle();

        if (methodName != null) {
            view.setOnClickListener(new FragmentClickListener(mFragment, methodName));
        }
        return view;
    }

    private static class FragmentClickListener implements OnClickListener {

        private final Object mFragment;
        private final String mMethodName;
        private Method mMethod;

        public FragmentClickListener(Object fragment, String methodName) {
            mFragment = fragment;
            mMethodName = methodName;
        }

        @Override
        public void onClick(View v) {
            if (mMethod == null) {
                Class<?> clazz = mFragment.getClass();
                try {
                    mMethod = clazz.getMethod(mMethodName, View.class);
                } catch (NoSuchMethodException e) {
                    throw new IllegalStateException(
                            "Cannot find public method " + mMethodName + "(View) on "
                                    + clazz + " for onClick");
                }
            }

            try {
                mMethod.invoke(mFragment, v);
            } catch (InvocationTargetException e) {
                throw new RuntimeException(e);
            } catch (IllegalAccessException e) {
                throw new AssertionError(e);
            }
        }
    }
}

Detach (move) subdirectory into separate Git repository

To add to Paul's answer, I found that to ultimately recover space, I have to push HEAD to a clean repository and that trims down the size of the .git/objects/pack directory.

i.e.

$ mkdir ...ABC.git
$ cd ...ABC.git
$ git init --bare

After the gc prune, also do:

$ git push ...ABC.git HEAD

Then you can do

$ git clone ...ABC.git

and the size of ABC/.git is reduced

Actually, some of the time consuming steps (e.g. git gc) aren't needed with the push to clean repository, i.e.:

$ git clone --no-hardlinks /XYZ /ABC
$ git filter-branch --subdirectory-filter ABC HEAD
$ git reset --hard
$ git push ...ABC.git HEAD

JCheckbox - ActionListener and ItemListener?

Both ItemListener as well as ActionListener, in case of JCheckBox have the same behaviour. However, major difference is ItemListener can be triggered by calling the setSelected(true) on the checkbox. As a coding practice do not register both ItemListener as well as ActionListener with the JCheckBox, in order to avoid inconsistency.

Android custom Row Item for ListView

create resource layout file list_item.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
          android:orientation="vertical"
          android:layout_width="match_parent"
          android:layout_height="wrap_content">
<TextView
        android:id="@+id/header_text"
        android:layout_height="0dp"
        android:layout_width="fill_parent"
        android:layout_weight="1"
        android:text="Header"
        />
<TextView
        android:id="@+id/item_text"
        android:layout_height="0dp"
        android:layout_width="fill_parent"
        android:layout_weight="1"
        android:text="dynamic text"
        />
</LinearLayout>

and initialise adaptor like this

adapter = new ArrayAdapter<String>(this, R.layout.list_item,R.id.item_text,data_array);

Get installed applications in a system

Use Windows Installer API!

It allows to make reliable enumeration of all programs. Registry is not reliable, but WMI is heavyweight.

How to select between brackets (or quotes or ...) in Vim?

This method of selection is built-in and well covered in the Vim help. It covers XML tags and more.

See :help text-objects.

What is syntax for selector in CSS for next element?

This is called the adjacent sibling selector, and it is represented by a plus sign...

h1.hc-reform + p {
  clear:both;
}

Note: this is not supported in IE6 or older.

Is it possible to write to the console in colour in .NET?

Yes. See this article. Here's an example from there:

Console.BackgroundColor = ConsoleColor.Blue;
Console.ForegroundColor = ConsoleColor.White;
Console.WriteLine("White on blue.");

enter image description here

How to get the start time of a long-running Linux process?

As a follow-up to Adam Matan's answer, the /proc/<pid> directory's time stamp as such is not necessarily directly useful, but you can use

awk -v RS=')' 'END{print $20}' /proc/12345/stat

to get the start time in clock ticks since system boot.1

This is a slightly tricky unit to use; see also convert jiffies to seconds for details.

awk -v ticks="$(getconf CLK_TCK)" 'NR==1 { now=$1; next }
    END { printf "%9.0f\n", now - ($20/ticks) }' /proc/uptime RS=')' /proc/12345/stat

This should give you seconds, which you can pass to strftime() to get a (human-readable, or otherwise) timestamp.

awk -v ticks="$(getconf CLK_TCK)" 'NR==1 { now=$1; next }
    END { print strftime("%c", systime() - (now-($20/ticks))) }' /proc/uptime RS=')' /proc/12345/stat

Updated with some fixes from Stephane Chazelas in the comments; thanks as always!

If you only have Mawk, maybe try

awk -v ticks="$(getconf CLK_TCK)" -v epoch="$(date +%s)" '
  NR==1 { now=$1; next }
  END { printf "%9.0f\n", epoch - (now-($20/ticks)) }' /proc/uptime RS=')' /proc/12345/stat |
xargs -i date -d @{}

1 man proc; search for starttime.

Is it possible to save HTML page as PDF using JavaScript or jquery?

Yes, Use jspdf To create a pdf file.

You can then turn it into a data URI and inject a download link into the DOM

You will however need to write the HTML to pdf conversion yourself.

Just use printer friendly versions of your page and let the user choose how he wants to print the page.

Edit: Apparently it has minimal support

So the answer is write your own PDF writer or get a existing PDF writer to do it for you (on the server).

Excel 2007 - Compare 2 columns, find matching values

You could fill the C Column with variations on the following formula:

=IF(ISERROR(MATCH(A1,$B:$B,0)),"",A1)

Then C would only contain values that were in A and C.

How to use jQuery with Angular?

Just write

declare var $:any;

after all import sections, you can use jQuery and include the jQuery library in your index.html page

<script src="https://code.jquery.com/jquery-3.3.1.js"></script>

it worked for me

Get output parameter value in ADO.NET

That looks more explicit for me:

int? id = outputIdParam.Value is DbNull ? default(int?) : outputIdParam.Value;

Adding form action in html in laravel

Your form is also missing '{{csrf_field()}}'

How to get ° character in a string in python?

Put this line at the top of your source

# -*- coding: utf-8 -*-

If your editor uses a different encoding, substitute for utf-8

Then you can include utf-8 characters directly in the source

Properly close mongoose's connection once you're done

You can set the connection to a variable then disconnect it when you are done:

var db = mongoose.connect('mongodb://localhost:27017/somedb');

// Do some stuff

db.disconnect();

What is the "right" JSON date format?

The prefered way is using 2018-04-23T18:25:43.511Z...

The picture below shows why this is the prefered way:

JSON Date

So as you see Date has a native Method toJSON, which return in this format and can be easily converted to Date again...

HTTP 415 unsupported media type error when calling Web API 2 endpoint

SOLVED
After banging my head on the wall for a couple days with this issue, it was looking like the problem had something to do with the content type negotiation between the client and server. I dug deeper into that using Fiddler to check the request details coming from the client app, here's a screenshot of the raw request as captured by fiddler:

Fiddler capture of http request from client app

What's obviously missing there is the Content-Type header, even though I was setting it as seen in the code sample in my original post. I thought it was strange that the Content-Type never came through even though I was setting it, so I had another look at my other (working) code calling a different Web API service, the only difference was that I happened to be setting the req.ContentType property prior to writing to the request body in that case. I made that change to this new code and that did it, the Content-Type was now showing up and I got the expected success response from the web service. The new code from my .NET client now looks like this:

req.Method = "POST"
req.ContentType = "application/json"
lstrPagingJSON = JsonSerializer(Of Paging)(lPaging)
bytData = Encoding.UTF8.GetBytes(lstrPagingJSON)
req.ContentLength = bytData.Length
reqStream = req.GetRequestStream()
reqStream.Write(bytData, 0, bytData.Length)
reqStream.Close()
'// Content-Type was being set here, causing the problem
'req.ContentType = "application/json"

That's all it was, the ContentType property just needed to be set prior to writing to the request body

I believe this behavior is because once content is written to the body it is streamed to the service endpoint being called, any other attributes pertaining to the request need to be set prior to that. Please correct me if I'm wrong or if this needs more detail.

Why does overflow:hidden not work in a <td>?

Well here is a solution for you but I don't really understand why it works:

<html><body>
  <div style="width: 200px; border: 1px solid red;">Test</div>
  <div style="width: 200px; border: 1px solid blue; overflow: hidden; height: 1.5em;">My hovercraft is full of eels.  These pretzels are making me thirsty.</div>
  <div style="width: 200px; border: 1px solid yellow; overflow: hidden; height: 1.5em;">
  This_is_a_terrible_example_of_thinking_outside_the_box.
  </div>
  <table style="border: 2px solid black; border-collapse: collapse; width: 200px;"><tr>
   <td style="width:200px; border: 1px solid green; overflow: hidden; height: 1.5em;"><div style="width: 200px; border: 1px solid yellow; overflow: hidden;">
    This_is_a_terrible_example_of_thinking_outside_the_box.
   </div></td>
  </tr></table>
</body></html>

Namely, wrapping the cell contents in a div.

Dynamically add child components in React

Firstly a warning: you should never tinker with DOM that is managed by React, which you are doing by calling ReactDOM.render(<SampleComponent ... />);

With React, you should use SampleComponent directly in the main App.

var App = require('./App.js');
var SampleComponent = require('./SampleComponent.js');
ReactDOM.render(<App/>, document.body);

The content of your Component is irrelevant, but it should be used like this:

var App = React.createClass({
    render: function() {
        return (
            <div>
                <h1>App main component! </h1>
                <SampleComponent name="SomeName"/>
            </div>
        );
    }
});

You can then extend your app component to use a list.

var App = React.createClass({
    render: function() {
        var componentList = [
            <SampleComponent name="SomeName1"/>,
            <SampleComponent name="SomeName2"/>
        ]; // Change this to get the list from props or state
        return (
            <div>
                <h1>App main component! </h1>
                {componentList}
            </div>
        );
    }
});

I would really recommend that you look at the React documentation then follow the "Get Started" instructions. The time you spend on that will pay off later.

https://facebook.github.io/react/index.html

Why I can't access remote Jupyter Notebook server?

if you are using Conda environment, you should set up config file again. And file location will be something like this. I did not setup config file after I created env in Conda and that was my connection problem.

C:\Users\syurt\AppData\Local\Continuum\anaconda3\envs\myenv\share\jupyter\jupyter_notebook_config.py