Programs & Examples On #Window handles

Winforms issue - Error creating window handle

The out of memory suggestion doesn't seem like a bad lead.

What is your program doing that it gets this error?

Is it creating a great many windows or controls? Does it create them programatically as opposed to at design time? If so, do you do this in a loop? Is that loop infinite? Are you consuming staggering boatloads of memory in some other way?

What happens when you watch the memory used by your application in task manager? Does it skyrocket to the moon? Or better yet, as suggested above use process monitor to dive into the details.

How to convert ASCII code (0-255) to its corresponding character?

An easier way of doing the same:

Type cast integer to character, let int n be the integer, then:

Char c=(char)n;
System.out.print(c)//char c will store the converted value.

How can I get name of element with jQuery?

If anyone is also looking for how to get the name of the HTML tag, you can use "tagName": $(this)[0].tagName

Difference between clean, gradlew clean

  1. ./gradlew clean

    Uses your project's gradle wrapper to execute your project's clean task. Usually, this just means the deletion of the build directory.

  2. ./gradlew clean assembleDebug

    Again, uses your project's gradle wrapper to execute the clean and assembleDebug tasks, respectively. So, it will clean first, then execute assembleDebug, after any non-up-to-date dependent tasks.

  3. ./gradlew clean :assembleDebug

    Is essentially the same as #2. The colon represents the task path. Task paths are essential in gradle multi-project's, not so much in this context. It means run the root project's assembleDebug task. Here, the root project is the only project.

  4. Android Studio --> Build --> Clean

    Is essentially the same as ./gradlew clean. See here.

For more info, I suggest taking the time to read through the Android docs, especially this one.

Installing Tomcat 7 as Service on Windows Server 2008

You can find the solution here!

Install the service named 'Tomcat7'

C:\>Tomcat\bin\service.bat install

There is a 2nd optional parameter that lets you specify the name of the service, as displayed in Windows services.

Install the service named 'MyTomcatService'

C:\>Tomcat\bin\service.bat install MyTomcatService

Flask Error: "Method Not Allowed The method is not allowed for the requested URL"

I had the same problem, and my solving was to replace :

return redirect(url_for('index'))

with

return render_template('indexo.html',data=Todos.query.all())

in my POST and DELETE route.

In Python, how do I split a string and keep the separators?

Another no-regex solution that works well on Python 3

# Split strings and keep separator
test_strings = ['<Hello>', 'Hi', '<Hi> <Planet>', '<', '']

def split_and_keep(s, sep):
   if not s: return [''] # consistent with string.split()

   # Find replacement character that is not used in string
   # i.e. just use the highest available character plus one
   # Note: This fails if ord(max(s)) = 0x10FFFF (ValueError)
   p=chr(ord(max(s))+1) 

   return s.replace(sep, sep+p).split(p)

for s in test_strings:
   print(split_and_keep(s, '<'))


# If the unicode limit is reached it will fail explicitly
unicode_max_char = chr(1114111)
ridiculous_string = '<Hello>'+unicode_max_char+'<World>'
print(split_and_keep(ridiculous_string, '<'))

Can't get ScriptManager.RegisterStartupScript in WebControl nested in UpdatePanel to work

DO NOT Use GUID For Key

ScriptManager.RegisterClientScriptBlock(this.Page, typeof(UpdatePanel) 
       Guid.NewGuid().ToString(), myScript, true);

and if you want to do that , call Something Like this function

 public static string GetGuidClear(string x)
 {
      return x.Replace("-", "").Replace("0", "").Replace("1", "")
              .Replace("2",  "").Replace("3", "").Replace("4", "")
              .Replace("5", "").Replace("6", "").Replace("7", "")
              .Replace("8", "").Replace("9", "");
 }

Image resizing in React Native

In my case I could not set 'width' and 'height' to null because I'm using TypeScript.

The way I fixed it was by setting them to '100%':

backgroundImage: {
    flex: 1,
    width: '100%',
    height: '100%',
    resizeMode: 'cover',        
}

What is the difference between DSA and RSA?

Btw, you cannot encrypt with DSA, only sign. Although they are mathematically equivalent (more or less) you cannot use DSA in practice as an encryption scheme, only as a digital signature scheme.

ADB not responding. You can wait more,or kill "adb.exe" process manually and click 'Restart'

I run netstat -nao | findstr 5037 in cmd.

enter image description here

As you see there is a process with id 3888. I kill it with taskkill /f /pid 3888 if you have more than one, kill all.

enter image description here

after that run adb with adb start-server, my adb run sucessfully.

enter image description here

What is "Advanced" SQL?

SELECT ... HAVING ... is a good start. Not many developers seem to understand how to use it.

'adb' is not recognized as an internal or external command, operable program or batch file

I had same problem when I define PATH below

C:\Program Files (x86)\Java\jre1.8.0_45\bin;C:\dev\sdk\android\platform-tools

and the problem solved when I bring adb root at first.

C:\dev\sdk\android\platform-tools;C:\Program Files (x86)\Java\jre1.8.0_45\bin

Jquery click event not working after append method

Use on :

$('#registered_participants').on('click', '.new_participant_form', function() {

So that the click is delegated to any element in #registered_participants having the class new_participant_form, even if it's added after you bound the event handler.

Find nearest latitude/longitude with an SQL query

The original answers to the question are good, but newer versions of mysql (MySQL 5.7.6 on) support geo queries, so you can now use built in functionality rather than doing complex queries.

You can now do something like:

select *, ST_Distance_Sphere( point ('input_longitude', 'input_latitude'), 
                              point(longitude, latitude)) * .000621371192 
          as `distance_in_miles` 
  from `TableName`
having `distance_in_miles` <= 'input_max_distance'
 order by `distance_in_miles` asc

The results are returned in meters. So if you want in KM simply use .001 instead of .000621371192 (which is for miles).

MySql docs are here

How to apply a CSS class on hover to dynamically generated submit buttons?

The most efficient selector you can use is an attribute selector.

 input[name="btnPage"]:hover {/*your css here*/}

Here's a live demo: http://tinkerbin.com/3G6B93Cb

Remove decimal values using SQL query

Simply update with a convert/cast to INT:

UPDATE YOUR_TABLE
SET YOUR_COLUMN = CAST(YOUR_COLUMN AS INT)
WHERE -- some condition is met if required

Or convert:

UPDATE YOUR_TABLE
SET YOUR_COLUMN = CONVERT(INT, YOUR_COLUMN)
WHERE -- some condition is met if required

To test you can do this:

SELECT YOUR_COLUMN AS CurrentValue,
       CAST(YOUR_COLUMN AS INT) AS NewValue
FROM YOUR_TABLE

Rename multiple files in cmd

This works for your specific case:

ren file?.txt "file? 1.1.txt" 

Detect whether a Python string is a number or a letter

For a string of length 1 you can simply perform isdigit() or isalpha()

If your string length is greater than 1, you can make a function something like..

def isinteger(a):
    try:
        int(a)
        return True
    except ValueError:
        return False

Execute JavaScript code stored as a string

function executeScript(source) {
    var script = document.createElement("script");
    script.onload = script.onerror = function(){ this.remove(); };
    script.src = "data:text/plain;base64," + btoa(source);
    document.body.appendChild(script);
}

executeScript("alert('Hello, World!');");

SQL Server 2005 Setting a variable to the result of a select query

You could also just put the first SELECT in a subquery. Since most optimizers will fold it into a constant anyway, there should not be a performance hit on this.

Incidentally, since you are using a predicate like this:

CONVERT(...) = CONVERT(...)

that predicate expression cannot be optimized properly or use indexes on the columns reference by the CONVERT() function.

Here is one way to make the original query somewhat better:

DECLARE @ooDate datetime
SELECT @ooDate = OO.Date FROM OLAP.OutageHours AS OO where OO.OutageID = 1

SELECT 
  COUNT(FF.HALID)
FROM
  Outages.FaultsInOutages AS OFIO 
  INNER JOIN Faults.Faults as FF ON 
    FF.HALID = OFIO.HALID 
WHERE
  FF.FaultDate >= @ooDate AND
  FF.FaultDate < DATEADD(day, 1, @ooDate) AND
  OFIO.OutageID = 1

This version could leverage in index that involved FaultDate, and achieves the same goal.

Here it is, rewritten to use a subquery to avoid the variable declaration and subsequent SELECT.

SELECT 
  COUNT(FF.HALID)
FROM
  Outages.FaultsInOutages AS OFIO 
  INNER JOIN Faults.Faults as FF ON 
    FF.HALID = OFIO.HALID 
WHERE
  CONVERT(varchar(10), FF.FaultDate, 126) = (SELECT CONVERT(varchar(10), OO.Date, 126) FROM OLAP.OutageHours AS OO where OO.OutageID = 1) AND
  OFIO.OutageID = 1

Note that this approach has the same index usage issue as the original, because of the use of CONVERT() on FF.FaultDate. This could be remedied by adding the subquery twice, but you would be better served with the variable approach in this case. This last version is only for demonstration.

Regards.

Drop all the tables, stored procedures, triggers, constraints and all the dependencies in one sql statement

You have to disable all triggers and constraints first.

EXEC sp_MSforeachtable @command1="ALTER TABLE ? NOCHECK CONSTRAINT ALL"

EXEC sp_MSforeachtable @command1="ALTER TABLE ? DISABLE TRIGGER ALL"

After that you can generate the scripts for deleting the objects as

SELECT 'Drop Table '+name FROM sys.tables WHERE type='U';

SELECT 'Drop Procedure '+name FROM  sys.procedures WHERE type='P';

Execute the statements generated.

Get the first element of each tuple in a list in Python

Use a list comprehension:

res_list = [x[0] for x in rows]

Below is a demonstration:

>>> rows = [(1, 2), (3, 4), (5, 6)]
>>> [x[0] for x in rows]
[1, 3, 5]
>>>

Alternately, you could use unpacking instead of x[0]:

res_list = [x for x,_ in rows]

Below is a demonstration:

>>> lst = [(1, 2), (3, 4), (5, 6)]
>>> [x for x,_ in lst]
[1, 3, 5]
>>>

Both methods practically do the same thing, so you can choose whichever you like.

Add characters to a string in Javascript

To use String.concat, you need to replace your existing text, since the function does not act by reference.

var text ="";
for (var member in list) {
        text = text.concat(list[member]);
}

Of course, the join() or += suggestions offered by others will work fine as well.

Insert/Update/Delete with function in SQL Server

Yes, you can!))

Disclaimer: This is not a solution, it is more of a hack to test out something. User-defined functions cannot be used to perform actions that modify the database state.

I found one way to make INSERT, UPDATE or DELETE in function using xp_cmdshell.

So you need just to replace the code inside @sql variable.

CREATE FUNCTION [dbo].[_tmp_func](@orderID NVARCHAR(50))
RETURNS INT
AS
BEGIN
DECLARE @sql varchar(4000), @cmd varchar(4000)
SELECT @sql = 'INSERT INTO _ord (ord_Code) VALUES (''' + @orderID + ''') '
SELECT @cmd = 'sqlcmd -S ' + @@servername +
              ' -d ' + db_name() + ' -Q "' + @sql + '"'
EXEC master..xp_cmdshell @cmd, 'no_output'
RETURN 1
END

Converting Numpy Array to OpenCV Array

This is what worked for me...

import cv2
import numpy as np

#Created an image (really an ndarray) with three channels 
new_image = np.ndarray((3, num_rows, num_cols), dtype=int)

#Did manipulations for my project where my array values went way over 255
#Eventually returned numbers to between 0 and 255

#Converted the datatype to np.uint8
new_image = new_image.astype(np.uint8)

#Separated the channels in my new image
new_image_red, new_image_green, new_image_blue = new_image

#Stacked the channels
new_rgb = np.dstack([new_image_red, new_image_green, new_image_blue])

#Displayed the image
cv2.imshow("WindowNameHere", new_rgbrgb)
cv2.waitKey(0)

Pythonic way to check if a file exists?

It seems to me that all other answers here (so far) fail to address the race-condition that occurs with their proposed solutions.

Any code where you first check for the files existence, and then, a few lines later in your program, you create it, runs the risk of the file being created while you weren't looking and causing you problems (or you causing the owner of "that other file" problems).

If you want to avoid this sort of thing, I would suggest something like the following (untested):

import os

def open_if_not_exists(filename):
    try:
        fd = os.open(filename, os.O_CREAT | os.O_EXCL | os.O_WRONLY)
    except OSError, e:
        if e.errno == 17:
            print e
            return None
        else:
            raise
    else:
        return os.fdopen(fd, 'w')

This should open your file for writing if it doesn't exist already, and return a file-object. If it does exists, it will print "Ooops" and return None (untested, and based solely on reading the python documentation, so might not be 100% correct).

Convert a String to a byte array and then back to the original String

You can do it like this.

String to byte array

String stringToConvert = "This String is 76 characters long and will be converted to an array of bytes";
byte[] theByteArray = stringToConvert.getBytes();

http://www.javadb.com/convert-string-to-byte-array

Byte array to String

byte[] byteArray = new byte[] {87, 79, 87, 46, 46, 46};
String value = new String(byteArray);

http://www.javadb.com/convert-byte-array-to-string

How to run a python script from IDLE interactive shell?

For example:

import subprocess

subprocess.call("C:\helloworld.py")

subprocess.call(["python", "-h"])

Opening XML page shows "This XML file does not appear to have any style information associated with it."

This XML file does not appear to have any style information associated with it. The document tree is shown below.

You will get this error in the client side when the client (the webbrowser) for some reason interprets the HTTP response content as text/xml instead of text/html and the parsed XML tree doesn't have any XML-stylesheet. In other words, the webbrowser incorrectly parsed the retrieved HTTP response content as XML instead of as HTML due to the wrong or missing HTTP response content type.

In case of JSF/Facelets files which have the default extension of .xhtml, that can in turn happen if the HTTP request hasn't invoked the FacesServlet and thus it wasn't able to parse the Facelets file and generate the desired HTML output based on the XHTML source code. Firefox is then merely guessing the HTTP response content type based on the .xhtml file extension which is in your Firefox configuration apparently by default interpreted as text/xml.

You need to make sure that the HTTP request URL, as you see in browser's address bar, matches the <url-pattern> of the FacesServlet as registered in webapp's web.xml, so that it will be invoked and be able to generate the desired HTML output based on the XHTML source code. If it's for example *.jsf, then you need to open the page by /some.jsf instead of /some.xhtml. Alternatively, you can also just change the <url-pattern> to *.xhtml. This way you never need to fiddle with virtual URLs.

See also:


Note thus that you don't actually need a XML stylesheet. This all was just misinterpretation by the webbrowser while trying to do its best to make something presentable out of the retrieved HTTP response content. It should actually have retrieved the properly generated HTML output, Firefox surely knows precisely how to deal with HTML content.

List directory in Go

ioutil.ReadDir is a good find, but if you click and look at the source you see that it calls the method Readdir of os.File. If you are okay with the directory order and don't need the list sorted, then this Readdir method is all you need.

Apache won't start in wamp

This solved the issue for me:

Right click on the WAMP system try icon -> Tools -> Reinstall all services

java.lang.ClassNotFoundException: sun.jdbc.odbc.JdbcOdbcDriver Exception occurring. Why?

Setup:

My OS windows 8 64bit
Eclipse version Standard/SDK Kepler Service Release 2
My JDK is jdk-8u5-windows-i586
My JRE is jre-8u5-windows-i586

This how I overcome my error.

At the very first my Class.forName("sun.jdbc.odbc.JdbcOdbcDriver") also didn't work. Then I login to this website and downloaded the UCanAccess 2.0.8 zip (as Mr.Gord Thompson said) file and unzip it.

Then you will also able to find these *.jar files in that unzip folder:

ucanaccess-2.0.8.jar
commons-lang-2.6.jar
commons-logging-1.1.1.jar
hsqldb.jar
jackcess-2.0.4.jar

Then what I did was I copied all these 5 files and paste them in these 2 locations:

C:\Program Files (x86)\eclipse\lib
C:\Program Files (x86)\eclipse\lib\ext

(I did that funny thing becoz I was unable to import these libraries to my project)

Then I reopen the eclipse with my project.then I see all that *.jar files in my project's JRE System Library folder.

Finally my code works.

public static void main(String[] args) 
{

    try
    {

        Connection conn=DriverManager.getConnection("jdbc:ucanaccess://C:\\Users\\Hasith\\Documents\\JavaDatabase1.mdb");
        Statement stment = conn.createStatement();
        String qry = "SELECT * FROM Table1";

        ResultSet rs = stment.executeQuery(qry);
        while(rs.next())
        {
            String id    = rs.getString("ID") ;
            String fname = rs.getString("Nama");

            System.out.println(id + fname);
        }
    }
    catch(Exception err)
    {
        System.out.println(err);
    }


    //System.out.println("Hasith Sithila");

}

When should static_cast, dynamic_cast, const_cast and reinterpret_cast be used?

While other answers nicely described all differences between C++ casts, I would like to add a short note why you should not use C-style casts (Type) var and Type(var).

For C++ beginners C-style casts look like being the superset operation over C++ casts (static_cast<>(), dynamic_cast<>(), const_cast<>(), reinterpret_cast<>()) and someone could prefer them over the C++ casts. In fact C-style cast is the superset and shorter to write.

The main problem of C-style casts is that they hide developer real intention of the cast. The C-style casts can do virtually all types of casting from normally safe casts done by static_cast<>() and dynamic_cast<>() to potentially dangerous casts like const_cast<>(), where const modifier can be removed so the const variables can be modified and reinterpret_cast<>() that can even reinterpret integer values to pointers.

Here is the sample.

int a=rand(); // Random number.

int* pa1=reinterpret_cast<int*>(a); // OK. Here developer clearly expressed he wanted to do this potentially dangerous operation.

int* pa2=static_cast<int*>(a); // Compiler error.
int* pa3=dynamic_cast<int*>(a); // Compiler error.

int* pa4=(int*) a; // OK. C-style cast can do such cast. The question is if it was intentional or developer just did some typo.

*pa4=5; // Program crashes.

The main reason why C++ casts were added to the language was to allow a developer to clarify his intentions - why he is going to do that cast. By using C-style casts which are perfectly valid in C++ you are making your code less readable and more error prone especially for other developers who didn't create your code. So to make your code more readable and explicit you should always prefer C++ casts over C-style casts.

Here is a short quote from Bjarne Stroustrup's (the author of C++) book The C++ Programming Language 4th edition - page 302.

This C-style cast is far more dangerous than the named conversion operators because the notation is harder to spot in a large program and the kind of conversion intended by the programmer is not explicit.

List of Timezone IDs for use with FindTimeZoneById() in C#?

DateTime dt;
TimeZoneInfo tzf;
tzf = TimeZoneInfo.FindSystemTimeZoneById("TimeZone String");
dt = TimeZoneInfo.ConvertTime(DateTime.Now, tzf);
lbltime.Text = dt.ToString();

How to make an anchor tag refer to nothing?

You can do it by

<a style='cursor:pointer' >Link</a>

PHP Array to CSV

Arrays of data are converted into csv 'text/csv' format by built in php function fputcsv takes care of commas, quotes and etc..
Look at
https://coderwall.com/p/zvzwwa/array-to-comma-separated-string-in-php
http://www.php.net/manual/en/function.fputcsv.php

Dynamically Changing log4j log level

For log4j 2 API , you can use

Logger logger = LogManager.getRootLogger();
Configurator.setAllLevels(logger.getName(), Level.getLevel(level));

C++ Cout & Cin & System "Ambiguous"

This kind of thing doesn't just magically happen on its own; you changed something! In industry we use version control to make regular savepoints, so when something goes wrong we can trace back the specific changes we made that resulted in that problem.

Since you haven't done that here, we can only really guess. In Visual Studio, Intellisense (the technology that gives you auto-complete dropdowns and those squiggly red lines) works separately from the actual C++ compiler under the bonnet, and sometimes gets things a bit wrong.

In this case I'd ask why you're including both cstdlib and stdlib.h; you should only use one of them, and I recommend the former. They are basically the same header, a C header, but cstdlib puts them in the namespace std in order to "C++-ise" them. In theory, including both wouldn't conflict but, well, this is Microsoft we're talking about. Their C++ toolchain sometimes leaves something to be desired. Any time the Intellisense disagrees with the compiler has to be considered a bug, whichever way you look at it!

Anyway, your use of using namespace std (which I would recommend against, in future) means that std::system from cstdlib now conflicts with system from stdlib.h. I can't explain what's going on with std::cout and std::cin.

Try removing #include <stdlib.h> and see what happens.

If your program is building successfully then you don't need to worry too much about this, but I can imagine the false positives being annoying when you're working in your IDE.

Activate a virtualenv with a Python script

You should create all your virtualenvs in one folder, such as virt.

Assuming your virtualenv folder name is virt, if not change it

cd
mkdir custom

Copy the below lines...

#!/usr/bin/env bash
ENV_PATH="$HOME/virt/$1/bin/activate"
bash --rcfile $ENV_PATH -i

Create a shell script file and paste the above lines...

touch custom/vhelper
nano custom/vhelper

Grant executable permission to your file:

sudo chmod +x custom/vhelper

Now export that custom folder path so that you can find it on the command-line by clicking tab...

export PATH=$PATH:"$HOME/custom"

Now you can use it from anywhere by just typing the below command...

vhelper YOUR_VIRTUAL_ENV_FOLDER_NAME

Suppose it is abc then...

vhelper abc

Count number of iterations in a foreach loop

If you just want to find out the number of elements in an array, use count. Now, to answer your question...

How to calculate how many items in a foreach?

$i = 0;
foreach ($Contents as $item) {
    $item[number];// if there are 15 $item[number] in this foreach, I want get the value : 15
    $i++;
}

If you only need the index inside the loop, you could use

foreach($Contents as $index=>$item) {
    // $index goes from 0 up to count($Contents) - 1
    // $item iterates over the elements
}

Can a PDF file's print dialog be opened with Javascript?

If you know how PDF files are structured (or are willing to spend a little while reading the spec), you can do it this way.

Use the Named Action "Print" in the OpenAction field of the Catalog object; the "Print" action is undocumented, but Acrobat Reader and most of the other major readers understand it. A nice benefit of this approach is that you don't get any JavaScript warnings. See here for details: http://www.gnostice.com/nl_article.asp?id=157

To make it even shinier, I added a second Action, URI, directing the reader to go back to the page that originated the request. Then I attached this Action to the first Named action using its Next field. With content disposition set to "inline", this makes it so that when the user clicks on the print link:

  1. It opens up Adobe Reader in the same tab and loads the file
  2. It immediately shows the print dialog
  3. As soon as the Print dialog is closed (whether they hit "OK" or "cancel"), the browser tab goes back to the webpage

I was able to do all these changes in Ruby easily enough using only the File and IO modules; I opened the PDF I had generated with an external tool, followed the xref to the existing Catalog section, then appended a new section onto the PDF with an updated Catalog object containing my special OpenAction line, and also the new Action objects.

Because of PDF's incremental revision features, you don't have to make any changes to the existing data to do this, just append an additional section to the end.

Splitting string into multiple rows in Oracle

Without using connect by or regexp:

    with mytable as (
      select 108 name, 'test' project, 'Err1,Err2,Err3' error from dual
      union all
      select 109, 'test2', 'Err1' from dual
    )
    ,x as (
      select name
      ,project
      ,','||error||',' error
      from mytable
    )
    ,iter as (SELECT rownum AS pos
        FROM all_objects
    )
    select x.name,x.project
    ,SUBSTR(x.error
      ,INSTR(x.error, ',', 1, iter.pos) + 1
      ,INSTR(x.error, ',', 1, iter.pos + 1)-INSTR(x.error, ',', 1, iter.pos)-1
    ) error
    from x, iter
    where iter.pos < = (LENGTH(x.error) - LENGTH(REPLACE(x.error, ','))) - 1;

How to make a list of n numbers in Python and randomly select any number?

You don't need to count stuff if you want to pick a random element. Just use random.choice() and pass your iterable:

import random
items = ['foo', 'bar', 'baz']
print random.choice(items)

If you really have to count them, use random.randint(1, count+1).

Finding the 'type' of an input element

If you want to check the type of input within form, use the following code:

<script>
    function getFind(obj) {
    for (i = 0; i < obj.childNodes.length; i++) {
        if (obj.childNodes[i].tagName == "INPUT") {
            if (obj.childNodes[i].type == "text") {
                alert("this is Text Box.")
            }
            if (obj.childNodes[i].type == "checkbox") {
                alert("this is CheckBox.")
            }
            if (obj.childNodes[i].type == "radio") {
                alert("this is Radio.")
            }
        }
        if (obj.childNodes[i].tagName == "SELECT") {
            alert("this is Select")
        }
    }
}
</script>     

<script>    
    getFind(document.myform);  
</script>

laravel Unable to prepare route ... for serialization. Uses Closure

Check your routes/web.php and routes/api.php

Laravel comes with default route closure in routes/web.php:

Route::get('/', function () {
    return view('welcome');
});

and routes/api.php

Route::middleware('auth:api')->get('/user', function (Request $request) {
    return $request->user();
});

if you remove that then try again to clear route cache.

How to set the title text color of UIButton?

Swift UI solution

Button(action: {}) {
            Text("Button")
        }.foregroundColor(Color(red: 1.0, green: 0.0, blue: 0.0))

Swift 3, Swift 4, Swift 5

to improve comments. This should work:

button.setTitleColor(.red, for: .normal)

Capture characters from standard input without waiting for enter to be pressed

The closest thing to portable is to use the ncurses library to put the terminal into "cbreak mode". The API is gigantic; the routines you'll want most are

  • initscr and endwin
  • cbreak and nocbreak
  • getch

Good luck!

Deploying just HTML, CSS webpage to Tomcat

Here's my setup: I am on Ubuntu 9.10.

Now, Here's what I did.

  1. Create a folder named "tomcat6-myapp" in /usr/share.
  2. Create a folder "myapp" under /usr/share/tomcat6-myapp.
  3. Copy the HTML file (that I need to deploy) to /usr/share/tomcat6-myapp/myapp. It must be named index.html.
  4. Go to /etc/tomcat6/Catalina/localhost.
  5. Create an xml file "myapp.xml" (i guess it must have the same name as the name of the folder in step 2) inside /etc/tomcat6/Catalina/localhost with the following contents.

    < Context path="/myapp" docBase="/usr/share/tomcat6-myapp/myapp" />
    
  6. This xml is called the 'Deployment Descriptor' which Tomcat reads and automatically deploys your app named "myapp".

  7. Now go to http://localhost:8080/myapp in your browser - the index.html gets picked up by tomcat and is shown.

I hope this helps!

How do I perform query filtering in django templates

I run into this problem on a regular basis and often use the "add a method" solution. However, there are definitely cases where "add a method" or "compute it in the view" don't work (or don't work well). E.g. when you are caching template fragments and need some non-trivial DB computation to produce it. You don't want to do the DB work unless you need to, but you won't know if you need to until you are deep in the template logic.

Some other possible solutions:

  1. Use the {% expr <expression> as <var_name> %} template tag found at http://www.djangosnippets.org/snippets/9/ The expression is any legal Python expression with your template's Context as your local scope.

  2. Change your template processor. Jinja2 (http://jinja.pocoo.org/2/) has syntax that is almost identical to the Django template language, but with full Python power available. It's also faster. You can do this wholesale, or you might limit its use to templates that you are working on, but use Django's "safer" templates for designer-maintained pages.

IE8 crashes when loading website - res://ieframe.dll/acr_error.htm

If the errors are caused by malware or spyware rogue extensions (especially those trying to spy on facebook account/pwd), which is perfectly possible, and this will happen anyway in the wild world, there is basically nothing you can do.

The best you can do is validate your site on various standard installations and browsers, including standard 3rd parties (like Adobe's flash, etc.), and add a help pages on your site to help your end user sort these kind of problems out by themselves.

Detect current device with UI_USER_INTERFACE_IDIOM() in Swift

Try this for check current device is iPhone or iPad:

Swift 5

struct Device {
    static let IS_IPAD = UIDevice.current.userInterfaceIdiom == .pad
    static let IS_IPHONE = UIDevice.current.userInterfaceIdiom == .phone
}

Use:

if(Device.IS_IPHONE){
    // device is iPhone
}if(Device.IS_IPAD){
    // device is iPad (or a Mac running under macOS Catalyst)
}else{
    // other
}

How to reset db in Django? I get a command 'reset' not found error

If you want to clean the whole database, you can use: python manage.py flush If you want to clean database table of a Django app, you can use: python manage.py migrate appname zero

Check if at least two out of three booleans are true

return 1 << $a << $b << $c >= 1 << 2;

Difference between View and ViewGroup in Android

A View object is a component of the user interface (UI) like a button or a text box, and it's also called widget.

A ViewGroup object is a layout, that is, a container of other ViewGroup objects (layouts) and View objects (widgets). It's possible to have a layout inside another layout. It's called nested layout but it can increase the time needed to draw the user interface.

The user interface for an app is built using a hierarchy of ViewGroup and View objects. In Android Studio it is possible to use the Component Tree window to visualise this hierarchy.

The Layout Editor in Android Studio can be used to drag and drop View objects (widgets) in the layout. It simplifies the creation of a layout.

Can I use Twitter Bootstrap and jQuery UI at the same time?

Because this is the top result on google on jquery ui and bootstrap.js I decided to add this as community wiki.

I am using:

  • Bootstrap v3.2.0
  • jquery-2.1.0
  • jquery-ui-1.10.3

and somehow when I include bootstrap.js it disables the dropdown of the jquery ui autocomplete.

my three workarounds:

  • exclude bootstrap.js
  • or more to typeahead lib
  • move from bootstrap.js to bootstrap.min.js (strange, but worked for me)

css divide width 100% to 3 column

2018 Update This is the method I use width: 33%; width: calc(33.33% - 20px); The first 33% is for browsers that do not support calc() inside the width property, the second would need to be vendor prefixed with -webkit- and -moz- for the best possible cross-browser support.

#c1, #c2, #c3 {
    margin: 10px; //not needed, but included to demonstrate the effect of having a margin with calc() widths/heights
    width: 33%; //fallback for browsers not supporting calc() in the width property
    width: -webkit-calc(33.33% - 20px); //We minus 20px from 100% if we're using the border-box box-sizing to account for our 10px margin on each side.
    width: -moz-calc(33.33% - 20px);
    width: calc(33.33% - 20px);
}

tl;dr account for your margin

HTTP response header content disposition for attachments

This has nothing to do with the MIME type, but the Content-Disposition header, which should be something like:

Content-Disposition: attachment; filename=genome.jpeg;

Make sure it is actually correctly passed to the client (not filtered by the server, proxy or something). Also you could try to change the order of writing headers and set them before getting output stream.

Bootstrap 3 offset on right not left

Since Google seems to like this answer...

If you're looking to match Bootstrap 4's naming convention, i.e. offset-*-#, here's that modification:

.offset-right-12 {
  margin-right: 100%;
}
.offset-right-11 {
  margin-right: 91.66666667%;
}
.offset-right-10 {
  margin-right: 83.33333333%;
}
.offset-right-9 {
  margin-right: 75%;
}
.offset-right-8 {
  margin-right: 66.66666667%;
}
.offset-right-7 {
  margin-right: 58.33333333%;
}
.offset-right-6 {
  margin-right: 50%;
}
.offset-right-5 {
  margin-right: 41.66666667%;
}
.offset-right-4 {
  margin-right: 33.33333333%;
}
.offset-right-3 {
  margin-right: 25%;
}
.offset-right-2 {
  margin-right: 16.66666667%;
}
.offset-right-1 {
  margin-right: 8.33333333%;
}
.offset-right-0 {
  margin-right: 0;
}
@media (min-width: 576px) {
  .offset-sm-right-12 {
    margin-right: 100%;
  }
  .offset-sm-right-11 {
    margin-right: 91.66666667%;
  }
  .offset-sm-right-10 {
    margin-right: 83.33333333%;
  }
  .offset-sm-right-9 {
    margin-right: 75%;
  }
  .offset-sm-right-8 {
    margin-right: 66.66666667%;
  }
  .offset-sm-right-7 {
    margin-right: 58.33333333%;
  }
  .offset-sm-right-6 {
    margin-right: 50%;
  }
  .offset-sm-right-5 {
    margin-right: 41.66666667%;
  }
  .offset-sm-right-4 {
    margin-right: 33.33333333%;
  }
  .offset-sm-right-3 {
    margin-right: 25%;
  }
  .offset-sm-right-2 {
    margin-right: 16.66666667%;
  }
  .offset-sm-right-1 {
    margin-right: 8.33333333%;
  }
  .offset-sm-right-0 {
    margin-right: 0;
  }
}
@media (min-width: 768px) {
  .offset-md-right-12 {
    margin-right: 100%;
  }
  .offset-md-right-11 {
    margin-right: 91.66666667%;
  }
  .offset-md-right-10 {
    margin-right: 83.33333333%;
  }
  .offset-md-right-9 {
    margin-right: 75%;
  }
  .offset-md-right-8 {
    margin-right: 66.66666667%;
  }
  .offset-md-right-7 {
    margin-right: 58.33333333%;
  }
  .offset-md-right-6 {
    margin-right: 50%;
  }
  .offset-md-right-5 {
    margin-right: 41.66666667%;
  }
  .offset-md-right-4 {
    margin-right: 33.33333333%;
  }
  .offset-md-right-3 {
    margin-right: 25%;
  }
  .offset-md-right-2 {
    margin-right: 16.66666667%;
  }
  .offset-md-right-1 {
    margin-right: 8.33333333%;
  }
  .offset-md-right-0 {
    margin-right: 0;
  }
}
@media (min-width: 992px) {
  .offset-lg-right-12 {
    margin-right: 100%;
  }
  .offset-lg-right-11 {
    margin-right: 91.66666667%;
  }
  .offset-lg-right-10 {
    margin-right: 83.33333333%;
  }
  .offset-lg-right-9 {
    margin-right: 75%;
  }
  .offset-lg-right-8 {
    margin-right: 66.66666667%;
  }
  .offset-lg-right-7 {
    margin-right: 58.33333333%;
  }
  .offset-lg-right-6 {
    margin-right: 50%;
  }
  .offset-lg-right-5 {
    margin-right: 41.66666667%;
  }
  .offset-lg-right-4 {
    margin-right: 33.33333333%;
  }
  .offset-lg-right-3 {
    margin-right: 25%;
  }
  .offset-lg-right-2 {
    margin-right: 16.66666667%;
  }
  .offset-lg-right-1 {
    margin-right: 8.33333333%;
  }
  .offset-lg-right-0 {
    margin-right: 0;
  }
}
@media (min-width: 1200px) {
  .offset-xl-right-12 {
    margin-right: 100%;
  }
  .offset-xl-right-11 {
    margin-right: 91.66666667%;
  }
  .offset-xl-right-10 {
    margin-right: 83.33333333%;
  }
  .offset-xl-right-9 {
    margin-right: 75%;
  }
  .offset-xl-right-8 {
    margin-right: 66.66666667%;
  }
  .offset-xl-right-7 {
    margin-right: 58.33333333%;
  }
  .offset-xl-right-6 {
    margin-right: 50%;
  }
  .offset-xl-right-5 {
    margin-right: 41.66666667%;
  }
  .offset-xl-right-4 {
    margin-right: 33.33333333%;
  }
  .offset-xl-right-3 {
    margin-right: 25%;
  }
  .offset-xl-right-2 {
    margin-right: 16.66666667%;
  }
  .offset-xl-right-1 {
    margin-right: 8.33333333%;
  }
  .offset-xl-right-0 {
    margin-right: 0;
  }
}

How to generate entire DDL of an Oracle schema (scriptable)?

The get_ddl procedure for a PACKAGE will return both spec AND body, so it will be better to change the query on the all_objects so the package bodies are not returned on the select.

So far I changed the query to this:

SELECT DBMS_METADATA.GET_DDL(REPLACE(object_type, ' ', '_'), object_name, owner)
FROM all_OBJECTS
WHERE (OWNER = 'OWNER1')
and object_type not like '%PARTITION'
and object_type not like '%BODY'
order by object_type, object_name;

Although other changes might be needed depending on the object types you are getting...

includes() not working in all browsers

import 'core-js/es7/array' 

into polyfill.ts worked for me.

SQL Server 2012 can't start because of a login failure

The answer to this may be identical to the problem with full blown SQL Server (NTService\MSSQLSERVER) and this is to reset the password. The ironic thing is, there is no password.

Steps are:

  • Right click on the Service in the Services mmc
  • Click Properties
  • Click on the Log On tab
  • The password fields will appear to have entries in them...
  • Blank out both Password fields
  • Click "OK"

This should re-grant access to the service and it should start up again. Weird?

NOTE: if the problem comes back after a few hours or days, then you probably have a group policy which is overriding your settings and it's coming and taking the right away again.

How to find a text inside SQL Server procedures / triggers?

Just wrote this for generic full outer cross ref

create table #XRefDBs(xtype varchar(2),SourceDB varchar(100), Object varchar(100), RefDB varchar(100))

declare @sourcedbname varchar(100),
        @searchfordbname varchar(100),
        @sql nvarchar(4000)
declare curs cursor for
    select name 
    from sysdatabases
    where dbid>4
open curs
fetch next from curs into @sourcedbname
while @@fetch_status=0
    begin
    print @sourcedbname
    declare curs2 cursor for 
        select name 
        from sysdatabases
        where dbid>4
        and name <> @sourcedbname
    open curs2
    fetch next from curs2 into @searchfordbname
    while @@fetch_status=0
        begin
        print @searchfordbname
        set @sql = 
        'INSERT INTO #XRefDBs (xtype,SourceDB,Object, RefDB)
        select DISTINCT o.xtype,'''+@sourcedbname+''', o.name,'''+@searchfordbname+'''
        from '+@sourcedbname+'.dbo.syscomments c
        join '+@sourcedbname+'.dbo.sysobjects o on c.id=o.id
        where o.xtype in (''V'',''P'',''FN'',''TR'')
        and (text like ''%'+@searchfordbname+'.%''
          or text like ''%'+@searchfordbname+'].%'')'
        print @sql
        exec sp_executesql @sql
        fetch next from curs2 into @searchfordbname
        end
    close curs2
    deallocate curs2
    fetch next from curs into @sourcedbname
    end
close curs
deallocate curs

select * from #XRefDBs

change html input type by JS?

I had to add a '.value' to the end of Evert's code to get it working.

Also I combined it with a browser check so that input type="number" field is changed to type="text" in Chrome since 'formnovalidate' doesn't seem to work right now.

if (navigator.userAgent.toLowerCase().indexOf('chrome') > -1)
    document.getElementById("input_id").attributes["type"].value = "text";

Round integers to the nearest 10

I wanted to do the same thing, but with 5 instead of 10, and came up with a simple function. Hope it's useful:

def roundToFive(num):
    remaining = num % 5
    if remaining in range(0, 3):
        return num - remaining
    return num + (5 - remaining)

Selenium Webdriver move mouse to Point

Robot robot = new Robot();
robot.mouseMove(coordinates.x,coordinates.y+80);

Rotbot is good solution. It works for me.

Best way to disable button in Twitter's Bootstrap

For input and button:

$('button').prop('disabled', true);

For anchor:

$('a').attr('disabled', true);

Checked in firefox, chrome.

See http://jsfiddle.net/czL54/2/

What is Gradle in Android Studio?

by @Brian Gardner:

Gradle is an extensive build tool and dependency manager for programming projects. It has a domain specific language based on Groovy. Gradle also provides build-by-convention support for many types of projects including Java, Android and Scala.

Feature of Gradle:

  1. Dependency Management
  2. Using Ant from Gradle
  3. Gradle Plugins
  4. Java Plugin
  5. Android Plugin
  6. Multi-Project Builds

Why does this iterative list-growing code give IndexError: list assignment index out of range?

You could use a dictionary (similar to an associative array) for j

i = [1, 2, 3, 5, 8, 13]
j = {} #initiate as dictionary
k = 0

for l in i:
    j[k] = l
    k += 1

print(j)

will print :

{0: 1, 1: 2, 2: 3, 3: 5, 4: 8, 5: 13}

Copy rows from one table to another, ignoring duplicates

The solution that worked for me with PHP / PDO.

public function createTrainingDatabase($p_iRecordnr){
// Methode: Create an database envirioment for a student by copying the original
// @parameter: $p_iRecordNumber,    type:integer,   scope:local
// @var: $this->sPdoQuery,          type:string,    scope:member 
// @var: $bSuccess,                 type:boolean,   scope:local
// @var: $aTables,                  type:array,     scope:local
// @var: $iUsernumber,              type:integer,   scope:local
// @var: $sNewDBName,               type:string,    scope:local
// @var: $iIndex,                   type:integer,   scope:local 

// -- Create first the name of the new database --
$aStudentcard = $this->fetchUsercardByRecordnr($p_iRecordnr);
$iUserNumber = $aStudentcard[0][3];
$sNewDBName = $_SESSION['DB_name']."_".$iUserNumber;
// -- Then create the new database  --
$this->sPdoQuery = "CREATE DATABASE `".$sNewDBName."`;";
$this->PdoSqlReturnTrue();
// -- Create an array with the tables you want to be copied --
$aTables = array('1eTablename','2ndTablename','3thTablename');
// -- Populate the database --
for ($iIndex = 0; $iIndex < count($aTables); $iIndex++) 
{
 // -- Create the table --
    $this->sPdoQuery = "CREATE TABLE `".$sNewDBName."`.`".$aTables[$iIndex]."` LIKE `".$_SESSION['DB_name']."`.`".$aTables[$iIndex]."`;";
    $bSuccess = $this->PdoSqlReturnTrue();
    if(!$bSuccess ){echo("Could not create table: ".$aTables[$iIndex]."<BR>");}
    else{echo("Created the table ".$aTables[$iIndex]."<BR>");}
    // -- Fill the table --
    $this->sPdoQuery = "REPLACE `".$sNewDBName."`.`".$aTables[$iIndex]."` SELECT * FROM `".$_SESSION['DB_name']."`.`".$aTables[$iIndex]."`";
    $bSuccess = $this->PdoSqlReturnTrue();
    if(!$bSuccess ){echo("Could not fill table: ".$aTables[$iIndex]."<BR>");}
    else{echo("Filled table ".$aTables[$index]."<BR>");}
}

}

How to install XCODE in windows 7 platform?

X-code is primarily made for OS-X or iPhone development on Mac systems. Versions for Windows are not available. However this might help!

There is no way to get Xcode on Windows; however you can use a different SDK like Corona instead although it will not use Objective-C (I believe it uses Lua). I have however heard that it is horrible to use.

Source: classroomm.com

No Title Bar Android Theme

To Hide the Action Bar add the below code in Values/Styles

<style name="CustomActivityThemeNoActionBar" parent="@android:style/Theme.Holo.Light">
    <item name="android:windowActionBar">false</item>
    <item name="android:windowNoTitle">true</item>
</style>

Then in your AndroidManifest.xml file add the below code in the required activity

<activity
        android:name="com.newbelievers.android.NBMenu"
        android:label="@string/title_activity_nbmenu"
        android:theme="@style/CustomActivityThemeNoActionBar">
</activity>

MySQL: Large VARCHAR vs. TEXT?

Varchar is for small data like email addresses, while Text is for much bigger data like news articles, Blob for binary data such as images.

The performance of Varchar is more powerful because it runs completely from memory, but this will not be the case if data is too big like varchar(4000) for example.

Text, on the other hand, does not stick to memory and is affected by disk performance, but you can avoid that by separating text data in a separate table and apply a left join query to retrieve text data.

Blob is much slower so use it only if you don't have much data like 10000 images which will cost 10000 records.

Follow these tips for maximum speed and performance:

  1. Use varchar for name, titles, emails

  2. Use Text for large data

  3. Separate text in different tables

  4. Use Left Join queries on an ID such as a phone number

  5. If you are going to use Blob apply the same tips as in Text

This will make queries cost milliseconds on tables with data >10 M and size up to 10GB guaranteed.

How can I add an item to a ListBox in C# and WinForms?

The way I do this - using the format Event

  MyClass c = new MyClass();
  listBox1.Items.Add(c);

  private void listBox1_Format(object sender, ListControlConvertEventArgs e)
    {
        if(e.ListItem is MyClass)
        {
            e.Value = ((MyClass)e.ListItem).ToString();
        }
        else
        {
            e.Value = "Unknown item added";
        }
    }

e.Value being the Display Text

Then you can attempt to cast the SelectedItem to MyClass to get access to anything you had in there.
Also note, you can use anything (that inherits from object anyway(which is pretty much everything)) in the Items Collection.

When to use .First and when to use .FirstOrDefault with LINQ?

linq many ways to implement single simple query on collections, just we write joins in sql, a filter can be applied first or last depending on the need and necessity.

Here is an example where we can find an element with a id in a collection. To add more on this, methods First, FirstOrDefault, would ideally return same when a collection has at least one record. If, however, a collection is okay to be empty. then First will return an exception but FirstOrDefault will return null or default. For instance, int will return 0. Thus usage of such is although said to be personal preference, but its better to use FirstOrDefault to avoid exception handling. here is an example where, we run over a collection of transactionlist

Char to int conversion in C

You can simply use theatol()function:

#include <stdio.h>
#include <stdlib.h>

int main() 
{
    const char *c = "5";
    int d = atol(c);
    printf("%d\n", d);

}

How to unpack and pack pkg file?

If you are experiencing errors during PKG installation following the accepted answer, I will give you another procedure that worked for me (please note the little changes to xar, cpio and mkbom commands):

mkdir Foo
cd Foo
xar -xf ../Foo.pkg
cd foo.pkg
cat Payload | gunzip -dc | cpio -i
# edit Foo.app/*
rm Payload
find ./Foo.app | cpio -o --format odc --owner 0:80 | gzip -c > Payload
mkbom -u 0 -g 80 Foo.app Bom # or edit Bom
# edit PackageInfo
rm -rf Foo.app
cd ..
xar --compression none -cf ../Foo-new.pkg

The resulted PKG will have no compression, cpio now uses odc format and specify the owner of the file as well as mkbom.

What does "all" stand for in a makefile?

The manual for GNU Make gives a clear definition for all in its list of standard targets.

If the author of the Makefile is following that convention then the target all should:

  1. Compile the entire program, but not build documentation.
  2. Be the the default target. As in running just make should do the same as make all.

To achieve 1 all is typically defined as a .PHONY target that depends on the executable(s) that form the entire program:

.PHONY : all
all : executable

To achieve 2 all should either be the first target defined in the make file or be assigned as the default goal:

.DEFAULT_GOAL := all

How to read file binary in C#?

Generally, I don't really see a possible way to do this. I've exhausted all of the options that the earlier comments gave you, and they don't seem to work. You could try this:

        `private void button1_Click(object sender, EventArgs e)
    {
        Stream myStream = null;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.InitialDirectory = "This PC\\Documents";
        openFileDialog1.Filter = "All Files (*.*)|*.*";
        openFileDialog1.FilterIndex = 1;
        openFileDialog1.RestoreDirectory = true;
        openFileDialog1.Title = "Open a file with code";

        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            string exeCode = string.Empty;
            using (BinaryReader br = new BinaryReader(File.OpenRead(openFileDialog1.FileName))) //Sets a new integer to the BinaryReader
            {
                br.BaseStream.Seek(0x4D, SeekOrigin.Begin); //The seek is starting from 0x4D
                exeCode = Encoding.UTF8.GetString(br.ReadBytes(1000000000)); //Reads as many bytes as it can from the beginning of the .exe file
            }
            using (BinaryReader br = new BinaryReader(File.OpenRead(openFileDialog1.FileName)))
                br.Close(); //Closes the BinaryReader. Without it, opening the file with any other command will result the error "This file is being used by another process".

            richTextBox1.Text = exeCode;
        }
    }`
  • That's the code for the "Open..." button, but here's the code for the "Save..." button:

    ` private void button2_Click(object sender, EventArgs e) { SaveFileDialog save = new SaveFileDialog();

        save.Filter = "All Files (*.*)|*.*";
        save.Title = "Save Your Changes";
        save.InitialDirectory = "This PC\\Documents";
        save.FilterIndex = 1;
    
        if (save.ShowDialog() == DialogResult.OK)
        {
    
            using (BinaryWriter bw = new BinaryWriter(File.OpenWrite(save.FileName))) //Sets a new integer to the BinaryReader
            {
                bw.BaseStream.Seek(0x4D, SeekOrigin.Begin); //The seek is starting from 0x4D
                bw.Write(richTextBox1.Text);
            }
        }
    }`
    
    • That's the save button. This works fine, but only shows the '!This cannot be run in DOS-Mode!' - Otherwise, if you can fix this, I don't know what to do.

    • My Site

Modify property value of the objects in list using Java 8 streams

You can use peek to do that.

List<Fruit> newList = fruits.stream()
    .peek(f -> f.setName(f.getName() + "s"))
    .collect(Collectors.toList());

How can I add raw data body to an axios request?

axios({
  method: 'post',     //put
  url: url,
  headers: {'Authorization': 'Bearer'+token}, 
  data: {
     firstName: 'Keshav', // This is the body part
     lastName: 'Gera'
  }
});

How to edit the legend entry of a chart in Excel?

Left Click on chart. «PivotTable Field List» will appear on right. On the right down quarter of PivotTable Field List (S Values), you see the names of the legends. Left Click on the legend name. Left Click on the «Value field settings». At the top there is «Source Name». You can’t change it. Below there is «Custom Name». Change the Custom Name as you wish. Now the legend name on the chart has the new name you gave.

SQL server ignore case in a where expression

You can force the case sensitive, casting to a varbinary like that:

SELECT * FROM myTable 
WHERE convert(varbinary, myField) = convert(varbinary, 'sOmeVal')

How can I setup & run PhantomJS on Ubuntu?

Or the latest - 32bit version Linux

sudo wget http://phantomjs.googlecode.com/files/phantomjs-1.9.2-linux-i686.tar.bz2

sudo ln -s /usr/local/share/phantomjs-1.9.2-linux-i686/bin/phantomjs /usr/local/share/phantomjs

sudo ln -s /usr/local/share/phantomjs-1.9.2-linux-i686/bin/phantomjs /usr/local/bin/phantomjs

sudo ln -s /usr/local/share/phantomjs-1.9.2-linux-i686/bin/phantomjs /usr/bin/phantomjs

Bitwise operation and usage

This example will show you the operations for all four 2 bit values:

10 | 12

1010 #decimal 10
1100 #decimal 12

1110 #result = 14

10 & 12

1010 #decimal 10
1100 #decimal 12

1000 #result = 8

Here is one example of usage:

x = raw_input('Enter a number:')
print 'x is %s.' % ('even', 'odd')[x&1]

How to edit the size of the submit button on a form?

Change height using:

input[type=submit] {
  border: none; /*rewriting standard style, it is necessary to be able to change the size*/
  height: 100px;
  width: 200px
}

Finding the handle to a WPF window

Well, instead of passing Application.Current.MainWindow, just pass a reference to whichever window it is you want: new WindowInteropHelper(this).Handle and so on.

Populate XDocument from String

How about this...?

TextReader tr = new StringReader("<Root>Content</Root>");
XDocument doc = XDocument.Load(tr);
Console.WriteLine(doc);

This was taken from the MSDN docs for XDocument.Load, found here...

http://msdn.microsoft.com/en-us/library/bb299692.aspx

Where Is Machine.Config?

32-bit

%windir%\Microsoft.NET\Framework\[version]\config\machine.config

64-bit

%windir%\Microsoft.NET\Framework64\[version]\config\machine.config 

[version] should be equal to v1.0.3705, v1.1.4322, v2.0.50727 or v4.0.30319.

v3.0 and v3.5 just contain additional assemblies to v2.0.50727 so there should be no config\machine.config. v4.5.x and v4.6.x are stored inside v4.0.30319.

Ignore fields from Java object dynamically while sending as JSON from Spring MVC

Add the @JsonIgnoreProperties("fieldname") annotation to your POJO.

Or you can use @JsonIgnore before the name of the field you want to ignore while deserializing JSON. Example:

@JsonIgnore
@JsonProperty(value = "user_password")
public String getUserPassword() {
    return userPassword;
}

GitHub example

Visual Studio Code cannot detect installed git

i have recently start visual studio code and have this issue and just write the exact path of executable git solve the issue .... here is the code ...

"git.path": "C:\Program Files\Git\bin\git.exe",

Java Replacing multiple different substring in a string at once (or in the most efficient way)

Rythm a java template engine now released with an new feature called String interpolation mode which allows you do something like:

String result = Rythm.render("@name is inviting you", "Diana");

The above case shows you can pass argument to template by position. Rythm also allows you to pass arguments by name:

Map<String, Object> args = new HashMap<String, Object>();
args.put("title", "Mr.");
args.put("name", "John");
String result = Rythm.render("Hello @title @name", args);

Note Rythm is VERY FAST, about 2 to 3 times faster than String.format and velocity, because it compiles the template into java byte code, the runtime performance is very close to concatentation with StringBuilder.

Links:

Converting NumPy array into Python List structure?

tolist() works fine even if encountered a nested array, say a pandas DataFrame;

my_list = [0,1,2,3,4,5,4,3,2,1,0]
my_dt = pd.DataFrame(my_list)
new_list = [i[0] for i in my_dt.values.tolist()]

print(type(my_list),type(my_dt),type(new_list))

AttributeError: 'dict' object has no attribute 'predictors'

The dict.items iterates over the key-value pairs of a dictionary. Therefore for key, value in dictionary.items() will loop over each pair. This is documented information and you can check it out in the official web page, or even easier, open a python console and type help(dict.items). And now, just as an example:

>>> d = {'hello': 34, 'world': 2999}
>>> for key, value in d.items():
...   print key, value
...
world 2999
hello 34

The AttributeError is an exception thrown when an object does not have the attribute you tried to access. The class dict does not have any predictors attribute (now you know where to check it :) ), and therefore it complains when you try to access it. As easy as that.

How can I include a YAML file inside another?

I think the solution used by @maxy-B looks great. However, it didn't succeed for me with nested inclusions. For example if config_1.yaml includes config_2.yaml, which includes config_3.yaml there was a problem with the loader. However, if you simply point the new loader class to itself on load, it works! Specifically, if we replace the old _include function with the very slightly modified version:

def _include(self, loader, node):                                    
     oldRoot = self.root                                              
     filename = os.path.join(self.root, loader.construct_scalar(node))
     self.root = os.path.dirname(filename)                           
     data = yaml.load(open(filename, 'r'), loader = IncludeLoader)                            
     self.root = oldRoot                                              
     return data

Upon reflection I agree with the other comments, that nested loading is not appropriate for yaml in general as the input stream may not be a file, but it is very useful!

Call asynchronous method in constructor?

The best solution is to acknowledge the asynchronous nature of the download and design for it.

In other words, decide what your application should look like while the data is downloading. Have the page constructor set up that view, and start the download. When the download completes update the page to display the data.

I have a blog post on asynchronous constructors that you may find useful. Also, some MSDN articles; one on asynchronous data-binding (if you're using MVVM) and another on asynchronous best practices (i.e., you should avoid async void).

How can I convert a date to GMT?

After searching for an hour or two ,I've found a simple solution below.

const date = new Date(`${date from client} GMT`);

inside double ticks, there is a date from client side plust GMT.

I'm first time commenting, constructive criticism will be welcomed.

Max or Default?

litt late, but I had the same concern...

Rephrasing your code from the original post, you want the max of the set S defined by

(From y In context.MyTable _
 Where y.MyField = value _
 Select y.MyCounter)

Taking in account your last comment

Suffice to say that I know I want 0 when there are no records to select from, which definitely has an impact on the eventual solution

I can rephrase your problem as: You want the max of {0 + S}. And it looks like the proposed solution with concat is semantically the right one :-)

var max = new[]{0}
          .Concat((From y In context.MyTable _
                   Where y.MyField = value _
                   Select y.MyCounter))
          .Max();

What is the purpose of the vshost.exe file?

It seems to be a long-running framework process for debugging (to decrease load times?). I discovered that when you start your application twice from the debugger often the same vshost.exe process will be used. It just unloads all user-loaded DLLs first. This does odd things if you are fooling around with API hooks from managed processes.

facet label font size

This should get you started:

R> qplot(hwy, cty, data = mpg) + 
       facet_grid(. ~ manufacturer) + 
       theme(strip.text.x = element_text(size = 8, colour = "orange", angle = 90))

See also this question: How can I manipulate the strip text of facet plots in ggplot2?

Ignoring NaNs with str.contains

I'm not 100% on why (actually came here to search for the answer), but this also works, and doesn't require replacing all nan values.

import pandas as pd
import numpy as np

df = pd.DataFrame([["foo1"], ["foo2"], ["bar"], [np.nan]], columns=['a'])

newdf = df.loc[df['a'].str.contains('foo') == True]

Works with or without .loc.

I have no idea why this works, as I understand it when you're indexing with brackets pandas evaluates whatever's inside the bracket as either True or False. I can't tell why making the phrase inside the brackets 'extra boolean' has any effect at all.

Path of currently executing powershell script

Split-Path $MyInvocation.MyCommand.Path -Parent

Getting absolute URLs using ASP.NET Core

You don't need to create an extension method for this

@Url.Action("Action", "Controller", values: null);

  • Action - Name of the action
  • Controller - Name of the controller
  • values - Object containing route values: aka GET parameters

There are also lots of other overloads to Url.Action you can use to generate links.

Copy data from another Workbook through VBA

There's very little reason not to open multiple workbooks in Excel. Key lines of code are:

Application.EnableEvents = False
Application.ScreenUpdating = False

...then you won't see anything whilst the code runs, and no code will run that is associated with the opening of the second workbook. Then there are...

Application.DisplayAlerts = False
Application.Calculation = xlManual

...so as to stop you getting pop-up messages associated with the content of the second file, and to avoid any slow re-calculations. Ensure you set back to True/xlAutomatic at end of your programming

If opening the second workbook is not going to cause performance issues, you may as well do it. In fact, having the second workbook open will make it very beneficial when attempting to debug your code if some of the secondary files do not conform to the expected format

Here is some expert guidance on using multiple Excel files that gives an overview of the different methods available for referencing data

An extension question would be how to cycle through multiple files contained in the same folder. You can use the Windows folder picker using:

With Application.FileDialog(msoFileDialogFolderPicker)
.Show
     If .Selected.Items.Count = 1 the InputFolder = .SelectedItems(1)
End With

FName = VBA.Dir(InputFolder)

Do While FName <> ""
'''Do function here
FName = VBA.Dir()
Loop

Hopefully some of the above will be of use

Detect when input has a 'readonly' attribute

Since JQuery 1.6, always use .prop() Read why here: http://api.jquery.com/prop/

if($('input').prop('readonly')){ }

.prop() can also be used to set the property

$('input').prop('readonly',true);

$('input').prop('readonly',false);

struct.error: unpack requires a string argument of length 4

The struct module mimics C structures. It takes more CPU cycles for a processor to read a 16-bit word on an odd address or a 32-bit dword on an address not divisible by 4, so structures add "pad bytes" to make structure members fall on natural boundaries. Consider:

struct {                   11
    char a;      012345678901
    short b;     ------------
    char c;      axbbcxxxdddd
    int d;
};

This structure will occupy 12 bytes of memory (x being pad bytes).

Python works similarly (see the struct documentation):

>>> import struct
>>> struct.pack('BHBL',1,2,3,4)
'\x01\x00\x02\x00\x03\x00\x00\x00\x04\x00\x00\x00'
>>> struct.calcsize('BHBL')
12

Compilers usually have a way of eliminating padding. In Python, any of =<>! will eliminate padding:

>>> struct.calcsize('=BHBL')
8
>>> struct.pack('=BHBL',1,2,3,4)
'\x01\x02\x00\x03\x04\x00\x00\x00'

Beware of letting struct handle padding. In C, these structures:

struct A {       struct B {
    short a;         int a;
    char b;          char b;
};               };

are typically 4 and 8 bytes, respectively. The padding occurs at the end of the structure in case the structures are used in an array. This keeps the 'a' members aligned on correct boundaries for structures later in the array. Python's struct module does not pad at the end:

>>> struct.pack('LB',1,2)
'\x01\x00\x00\x00\x02'
>>> struct.pack('LBLB',1,2,3,4)
'\x01\x00\x00\x00\x02\x00\x00\x00\x03\x00\x00\x00\x04'

How to return a struct from a function in C++?

studentType newStudent() // studentType doesn't exist here
{   
    struct studentType // it only exists within the function
    {
        string studentID;
        string firstName;
        string lastName;
        string subjectName;
        string courseGrade;

        int arrayMarks[4];

        double avgMarks;

    } newStudent;
...

Move it outside the function:

struct studentType
{
    string studentID;
    string firstName;
    string lastName;
    string subjectName;
    string courseGrade;

    int arrayMarks[4];

    double avgMarks;

};

studentType newStudent()
{
    studentType newStudent
    ...
    return newStudent;
}

What is the difference between HAVING and WHERE in SQL?

From here.

the SQL standard requires that HAVING must reference only columns in the GROUP BY clause or columns used in aggregate functions

as opposed to the WHERE clause which is applied to database rows

jQuery toggle animation

onmouseover="$('.play-detail').stop().animate({'height': '84px'},'300');" 

onmouseout="$('.play-detail').stop().animate({'height': '44px'},'300');"

Just put two stops -- one onmouseover and one onmouseout.

React.js: Wrapping one component into another

In addition to Sophie's answer, I also have found a use in sending in child component types, doing something like this:

var ListView = React.createClass({
    render: function() {
        var items = this.props.data.map(function(item) {
            return this.props.delegate({data:item});
        }.bind(this));
        return <ul>{items}</ul>;
    }
});

var ItemDelegate = React.createClass({
    render: function() {
        return <li>{this.props.data}</li>
    }
});

var Wrapper = React.createClass({    
    render: function() {
        return <ListView delegate={ItemDelegate} data={someListOfData} />
    }
});

Remove URL parameters without refreshing page

//Joraid code is working but i altered as below. it will work if your URL contain "?" mark or not
//replace URL in browser
if(window.location.href.indexOf("?") > -1) {
    var newUrl = refineUrl();
    window.history.pushState("object or string", "Title", "/"+newUrl );
}

function refineUrl()
{
    //get full url
    var url = window.location.href;
    //get url after/  
    var value = url = url.slice( 0, url.indexOf('?') );
    //get the part after before ?
    value  = value.replace('@System.Web.Configuration.WebConfigurationManager.AppSettings["BaseURL"]','');  
    return value;     
}

How can I "reset" an Arduino board?

If nothing helped then you should arrange one more board and try to flash it through the Arduino as ISP option as shown in Arduino as ISP and Arduino Bootloaders or From Arduino to a Microcontroller on a Breadboard.

Instead of a boot loader, you can select your own programs to flash via ISP.

How to launch PowerShell (not a script) from the command line

Set the default console colors and fonts:

http://poshcode.org/2220
From Windows PowerShell Cookbook (O'Reilly)
by Lee Holmes (http://www.leeholmes.com/guide)

Set-StrictMode -Version Latest

Push-Location
Set-Location HKCU:\Console
New-Item '.\%SystemRoot%_system32_WindowsPowerShell_v1.0_powershell.exe'
Set-Location '.\%SystemRoot%_system32_WindowsPowerShell_v1.0_powershell.exe'

New-ItemProperty . ColorTable00 -type DWORD -value 0x00562401
New-ItemProperty . ColorTable07 -type DWORD -value 0x00f0edee
New-ItemProperty . FaceName -type STRING -value "Lucida Console"
New-ItemProperty . FontFamily -type DWORD -value 0x00000036
New-ItemProperty . FontSize -type DWORD -value 0x000c0000
New-ItemProperty . FontWeight -type DWORD -value 0x00000190
New-ItemProperty . HistoryNoDup -type DWORD -value 0x00000000
New-ItemProperty . QuickEdit -type DWORD -value 0x00000001
New-ItemProperty . ScreenBufferSize -type DWORD -value 0x0bb80078
New-ItemProperty . WindowSize -type DWORD -value 0x00320078
Pop-Location

GET URL parameter in PHP

I was getting nothing for any $_GET["..."] (e.g print_r($_GET) gave an empty array) yet $_SERVER['REQUEST_URI'] showed stuff should be there. In the end it turned out that I was only getting to the web page because my .htaccess was redirecting it there (my 404 handler was the same .php file, and I had made a typo in the browser when testing).

Simply changing the name meant the same php code worked once the 404 redirection wasn't kicking in!

So there are ways $_GET can return nothing even though the php code may be correct.

How do I create a branch?

If you're repo is available via https, you can use this command to branch ...

svn copy https://host.example.com/repos/project/trunk \
       https://host.example.com/repos/project/branches/branch-name \
  -m "Creating a branch of project"

Error in Eclipse: "The project cannot be built until build path errors are resolved"

If you can't find the build path error, sometimes menu Project ? Clean... works like a charm.

How to return data from PHP to a jQuery ajax call

Yes, the way you are doing it is perfectly legitimate. To access that data on the client side, edit your success function to accept a parameter: data.

$.ajax({
    type: "POST",
    url: "somescript.php",
    datatype: "html",
    data: dataString,
    success: function(data) {
        doSomething(data);
    }
});

NoClassDefFoundError: org/slf4j/impl/StaticLoggerBinder

Copy all order entries of home folder .iml file into your /src/main/main.iml file. This will solve the problem.

Run react-native on android emulator

I had similar issue running emulator from android studio everytime, or on a physical device. Instead, you can quickly run android emulator from command line,

android avd

Once the emulator is running, you can check with adb devices if the emulator shows up. Then you can simply use react-native run-android to run the app on the emulator.

Make sure you've platform tools installed to be able to use adb. Or you can use

brew install android-platform-tools

Removing fields from struct or hiding them in JSON Response

Here is how I defined my structure.

type User struct {
    Username string  `json:"username" bson:"username"`
    Email    string  `json:"email" bson:"email"`
    Password *string `json:"password,omitempty" bson:"password"`
    FullName string  `json:"fullname" bson:"fullname"`
}

And inside my function set user.Password = nil for not to be Marshalled.

Codeigniter $this->db->order_by(' ','desc') result is not complete

$this->db1->where('tennant_id', $tennant_id);
$this->db1->order_by('id', 'DESC');
return $this->db1->get('courses')->result();

Best way of invoking getter by reflection

You can use Reflections framework for this

import static org.reflections.ReflectionUtils.*;
Set<Method> getters = ReflectionUtils.getAllMethods(someClass,
      withModifier(Modifier.PUBLIC), withPrefix("get"), withAnnotation(annotation));

How to set the java.library.path from Eclipse

Click Run
Click Debug ...
New Java Application
Click Arguments tab
in the 2nd box (VM Arguments) add the -D entry

-Xdebug -verbose:gc -Xbootclasspath/p:jar/vbjorb.jar;jar/oracle9.jar;classes;jar/mq.jar;jar/xml4j.jar -classpath -DORBInitRef=NameService=iioploc://10.101.2.94:8092/NameService  

etc...

Createuser: could not connect to database postgres: FATAL: role "tom" does not exist

On Windows use:

C:\PostgreSQL\pg10\bin>createuser -U postgres --pwprompt <USER>

Add --superuser or --createdb as appropriate.

See https://www.postgresql.org/docs/current/static/app-createuser.html for further options.

How to set RelativeLayout layout params in code not in xml?

Just a basic example:

RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
params.addRule(RelativeLayout.ALIGN_PARENT_LEFT, RelativeLayout.TRUE);
Button button1;
button1.setLayoutParams(params);

params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
params.addRule(RelativeLayout.RIGHT_OF, button1.getId());
Button button2;
button2.setLayoutParams(params);

As you can see, this is what you have to do:

  1. Create a RelativeLayout.LayoutParams object.
  2. Use addRule(int) or addRule(int, int) to set the rules. The first method is used to add rules that don't require values.
  3. Set the parameters to the view (in this case, to each button).

Visual Studio: How to show Overloads in IntelliSense?

Try the keyboard shortcut Ctrl-Shift-Space. This corresponds to Edit.ParameterInfo, in case you've changed the default.

Example:

descriptive screenshot, by jp2code

How can I combine flexbox and vertical scroll in a full-height app?

Flexbox spec editor here.

This is an encouraged use of flexbox, but there are a few things you should tweak for best behavior.

  • Don't use prefixes. Unprefixed flexbox is well-supported across most browsers. Always start with unprefixed, and only add prefixes if necessary to support it.

  • Since your header and footer aren't meant to flex, they should both have flex: none; set on them. Right now you have a similar behavior due to some overlapping effects, but you shouldn't rely on that unless you want to accidentally confuse yourself later. (Default is flex:0 1 auto, so they start at their auto height and can shrink but not grow, but they're also overflow:visible by default, which triggers their default min-height:auto to prevent them from shrinking at all. If you ever set an overflow on them, the behavior of min-height:auto changes (switching to zero rather than min-content) and they'll suddenly get squished by the extra-tall <article> element.)

  • You can simplify the <article> flex too - just set flex: 1; and you'll be good to go. Try to stick with the common values in https://drafts.csswg.org/css-flexbox/#flex-common unless you have a good reason to do something more complicated - they're easier to read and cover most of the behaviors you'll want to invoke.

Clone contents of a GitHub repository (without the folder itself)

to clone git repo into the current and empty folder (no git init) and if you do not use ssh:

git clone https://github.com/accountName/repoName.git .

TypeError: '<=' not supported between instances of 'str' and 'int'

Change

vote = input('Enter the name of the player you wish to vote for')

to

vote = int(input('Enter the name of the player you wish to vote for'))

You are getting the input from the console as a string, so you must cast that input string to an int object in order to do numerical operations.

Calling an API from SQL Server stored procedure

I think it would be easier using this CLR Stored procedure SQL-APIConsumer:

 exec [dbo].[APICaller_POST]
     @URL = 'http://localhost:5000/api/auth/login'
    ,@BodyJson = '{"Username":"gdiaz","Password":"password"}'

It has multiple procedures that allows you calling API that required a parameters and even passing multiples headers and tokens authentications.

enter image description here

enter image description here

How to count down in for loop?

In python, when you have an iterable, usually you iterate without an index:

letters = 'abcdef' # or a list, tupple or other iterable
for l in letters:
    print(l)

If you need to traverse the iterable in reverse order, you would do:

for l in letters[::-1]:
    print(l)

When for any reason you need the index, you can use enumerate:

for i, l in enumerate(letters, start=1): #start is 0 by default
    print(i,l)

You can enumerate in reverse order too...

for i, l in enumerate(letters[::-1])
    print(i,l)

ON ANOTHER NOTE...

Usually when we traverse an iterable we do it to apply the same procedure or function to each element. In these cases, it is better to use map:

If we need to capitilize each letter:

map(str.upper, letters)

Or get the Unicode code of each letter:

map(ord, letters)

No shadow by default on Toolbar?

actionbar_background.xml

    <item>
        <shape>
            <solid android:color="@color/black" />
            <corners android:radius="2dp" />
            <gradient
                android:startColor="@color/black"
                android:centerColor="@color/black"
                android:endColor="@color/white"
                android:angle="270" />
        </shape>
    </item>

    <item android:bottom="3dp" >
        <shape>

            <solid android:color="#ffffff" />
            <corners android:radius="1dp" />
        </shape>
    </item>
</layer-list>

add to actionbar_style background

<style name="Theme.ActionBar" parent="style/Widget.AppCompat.Light.ActionBar.Solid">
    <item name="background">@drawable/actionbar_background</item>
    <item name="android:elevation">0dp</item>
    <item name="android:windowContentOverlay">@null</item>
    <item name="android:layout_marginBottom">5dp</item>

name="displayOptions">useLogo|showHome|showTitle|showCustom

add to Basetheme

<style name="BaseTheme" parent="Theme.AppCompat.Light">
   <item name="android:homeAsUpIndicator">@drawable/home_back</item>
   <item name="actionBarStyle">@style/Theme.ActionBar</item>
</style>

insert vertical divider line between two nested divs, not full height

Can't think of a only css solution, but couldn't you just had a div between those 2 and set in the css the properties to look like a line like shown in the image? If you are using divs as they were table cells this is a pretty simple solution to the problem

Is there an auto increment in sqlite?

As of today — June 2018


Here is what official SQLite documentation has to say on the subject (bold & italic are mine):

  1. The AUTOINCREMENT keyword imposes extra CPU, memory, disk space, and disk I/O overhead and should be avoided if not strictly needed. It is usually not needed.

  2. In SQLite, a column with type INTEGER PRIMARY KEY is an alias for the ROWID (except in WITHOUT ROWID tables) which is always a 64-bit signed integer.

  3. On an INSERT, if the ROWID or INTEGER PRIMARY KEY column is not explicitly given a value, then it will be filled automatically with an unused integer, usually one more than the largest ROWID currently in use. This is true regardless of whether or not the AUTOINCREMENT keyword is used.

  4. If the AUTOINCREMENT keyword appears after INTEGER PRIMARY KEY, that changes the automatic ROWID assignment algorithm to prevent the reuse of ROWIDs over the lifetime of the database. In other words, the purpose of AUTOINCREMENT is to prevent the reuse of ROWIDs from previously deleted rows.

SQL Inner Join On Null Values

Basically you want to join two tables together where their QID columns are both not null, correct? However, you aren't enforcing any other conditions, such as that the two QID values (which seems strange to me, but ok). Something as simple as the following (tested in MySQL) seems to do what you want:

SELECT * FROM `Y` INNER JOIN `X` ON (`Y`.`QID` IS NOT NULL AND `X`.`QID` IS NOT NULL);

This gives you every non-null row in Y joined to every non-null row in X.

Update: Rico says he also wants the rows with NULL values, why not just:

SELECT * FROM `Y` INNER JOIN `X`;

Using app.config in .Net Core

  1. You can use Microsoft.Extensions.Configuration API with any .NET Core app, not only with ASP.NET Core app. Look into sample provided in the link, that shows how to read configs in the console app.

  2. In most cases, the JSON source (read as .json file) is the most suitable config source.

    Note: don't be confused when someone says that config file should be appsettings.json. You can use any file name, that is suitable for you and file location may be different - there are no specific rules.

    But, as the real world is complicated, there are a lot of different configuration providers:

    • File formats (INI, JSON, and XML)
    • Command-line arguments
    • Environment variables

    and so on. You even could use/write a custom provider.

  3. Actually, app.config configuration file was an XML file. So you can read settings from it using XML configuration provider (source on github, nuget link). But keep in mind, it will be used only as a configuration source - any logic how your app behaves should be implemented by you. Configuration Provider will not change 'settings' and set policies for your apps, but only read data from the file.

Adding elements to a collection during iteration

For examle we have two lists:

  public static void main(String[] args) {
        ArrayList a = new ArrayList(Arrays.asList(new String[]{"a1", "a2", "a3","a4", "a5"}));
        ArrayList b = new ArrayList(Arrays.asList(new String[]{"b1", "b2", "b3","b4", "b5"}));
        merge(a, b);
        a.stream().map( x -> x + " ").forEach(System.out::print);
    }
   public static void merge(List a, List b){
        for (Iterator itb = b.iterator(); itb.hasNext(); ){
            for (ListIterator it = a.listIterator() ; it.hasNext() ; ){
                it.next();
                it.add(itb.next());

            }
        }

    }

a1 b1 a2 b2 a3 b3 a4 b4 a5 b5

How to disable a particular checkstyle rule for a particular line of code?

I had difficulty with the answers above, potentially because I set the checkStyle warnings to be errors. What did work was SuppressionFilter: http://checkstyle.sourceforge.net/config_filters.html#SuppressionFilter

The drawback of this is that the line range is stored in a separate suppresssions.xml file, so an unfamiliar developer may not immediately make the connection.

How to redirect both stdout and stderr to a file

If you want to log to the same file:

command1 >> log_file 2>&1

If you want different files:

command1 >> log_file 2>> err_file

How to access parameters in a Parameterized Build?

To parameter variable add prefix "params." For example:

params.myParam

Don't forget: if you use some method of myParam, may be you should approve it in "Script approval".

How do I center text horizontally and vertically in a TextView?

I'm assuming you're using XML layout.

<TextView  
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:gravity="center"
    android:text="@string/**yourtextstring**"
/>

You can also use gravity center_vertical or center_horizontal according to your need.

and as @stealthcopter commented in java: .setGravity(Gravity.CENTER);

How to get URL parameters with Javascript?

function getURLParameter(name) {
  return decodeURIComponent((new RegExp('[?|&]' + name + '=' + '([^&;]+?)(&|#|;|$)').exec(location.search) || [null, ''])[1].replace(/\+/g, '%20')) || null;
}

So you can use:

myvar = getURLParameter('myvar');

How do I use arrays in C++?

Assignment

For no particular reason, arrays cannot be assigned to one another. Use std::copy instead:

#include <algorithm>

// ...

int a[8] = {2, 3, 5, 7, 11, 13, 17, 19};
int b[8];
std::copy(a + 0, a + 8, b);

This is more flexible than what true array assignment could provide because it is possible to copy slices of larger arrays into smaller arrays. std::copy is usually specialized for primitive types to give maximum performance. It is unlikely that std::memcpy performs better. If in doubt, measure.

Although you cannot assign arrays directly, you can assign structs and classes which contain array members. That is because array members are copied memberwise by the assignment operator which is provided as a default by the compiler. If you define the assignment operator manually for your own struct or class types, you must fall back to manual copying for the array members.

Parameter passing

Arrays cannot be passed by value. You can either pass them by pointer or by reference.

Pass by pointer

Since arrays themselves cannot be passed by value, usually a pointer to their first element is passed by value instead. This is often called "pass by pointer". Since the size of the array is not retrievable via that pointer, you have to pass a second parameter indicating the size of the array (the classic C solution) or a second pointer pointing after the last element of the array (the C++ iterator solution):

#include <numeric>
#include <cstddef>

int sum(const int* p, std::size_t n)
{
    return std::accumulate(p, p + n, 0);
}

int sum(const int* p, const int* q)
{
    return std::accumulate(p, q, 0);
}

As a syntactic alternative, you can also declare parameters as T p[], and it means the exact same thing as T* p in the context of parameter lists only:

int sum(const int p[], std::size_t n)
{
    return std::accumulate(p, p + n, 0);
}

You can think of the compiler as rewriting T p[] to T *p in the context of parameter lists only. This special rule is partly responsible for the whole confusion about arrays and pointers. In every other context, declaring something as an array or as a pointer makes a huge difference.

Unfortunately, you can also provide a size in an array parameter which is silently ignored by the compiler. That is, the following three signatures are exactly equivalent, as indicated by the compiler errors:

int sum(const int* p, std::size_t n)

// error: redefinition of 'int sum(const int*, size_t)'
int sum(const int p[], std::size_t n)

// error: redefinition of 'int sum(const int*, size_t)'
int sum(const int p[8], std::size_t n)   // the 8 has no meaning here

Pass by reference

Arrays can also be passed by reference:

int sum(const int (&a)[8])
{
    return std::accumulate(a + 0, a + 8, 0);
}

In this case, the array size is significant. Since writing a function that only accepts arrays of exactly 8 elements is of little use, programmers usually write such functions as templates:

template <std::size_t n>
int sum(const int (&a)[n])
{
    return std::accumulate(a + 0, a + n, 0);
}

Note that you can only call such a function template with an actual array of integers, not with a pointer to an integer. The size of the array is automatically inferred, and for every size n, a different function is instantiated from the template. You can also write quite useful function templates that abstract from both the element type and from the size.

What are .NET Assemblies?

MSDN has a good explanation:

Assemblies are the building blocks of .NET Framework applications; they form the fundamental unit of deployment, version control, reuse, activation scoping, and security permissions. An assembly is a collection of types and resources that are built to work together and form a logical unit of functionality. An assembly provides the common language runtime with the information it needs to be aware of type implementations. To the runtime, a type does not exist outside the context of an assembly.

Java image resize, maintain aspect ratio

Here we go:

Dimension imgSize = new Dimension(500, 100);
Dimension boundary = new Dimension(200, 200);

Function to return the new size depending on the boundary:

public static Dimension getScaledDimension(Dimension imgSize, Dimension boundary) {

    int original_width = imgSize.width;
    int original_height = imgSize.height;
    int bound_width = boundary.width;
    int bound_height = boundary.height;
    int new_width = original_width;
    int new_height = original_height;

    // first check if we need to scale width
    if (original_width > bound_width) {
        //scale width to fit
        new_width = bound_width;
        //scale height to maintain aspect ratio
        new_height = (new_width * original_height) / original_width;
    }

    // then check if we need to scale even with the new height
    if (new_height > bound_height) {
        //scale height to fit instead
        new_height = bound_height;
        //scale width to maintain aspect ratio
        new_width = (new_height * original_width) / original_height;
    }

    return new Dimension(new_width, new_height);
}

In case anyone also needs the image resizing code, here is a decent solution.

If you're unsure about the above solution, there are different ways to achieve the same result.

Hiding a form and showing another when a button is clicked in a Windows Forms application

i believe the following code will only run after form1 is closed

 while (true)
    {
        if (form1.Visible == false)
            form2.Show();
    }

Why not start your form2 from form1 instead?

Form2 form2 = new Form2();
 private void button1_Click_1(object sender, EventArgs e)
    {
        if (richTextBox1.Text != null)
        {
            form1.Visible=false;
            form2.Show();

        }
        else MessageBox.Show("Insert Attributes First !");

    }

'printf' with leading zeros in C

Your format specifier is incorrect. From the printf() man page on my machine:

0 A zero '0' character indicating that zero-padding should be used rather than blank-padding. A '-' overrides a '0' if both are used;

Field Width: An optional digit string specifying a field width; if the output string has fewer characters than the field width it will be blank-padded on the left (or right, if the left-adjustment indicator has been given) to make up the field width (note that a leading zero is a flag, but an embedded zero is part of a field width);

Precision: An optional period, '.', followed by an optional digit string giving a precision which specifies the number of digits to appear after the decimal point, for e and f formats, or the maximum number of characters to be printed from a string; if the digit string is missing, the precision is treated as zero;

For your case, your format would be %09.3f:

#include <stdio.h>

int main(int argc, char **argv)
{
  printf("%09.3f\n", 4917.24);
  return 0;
}

Output:

$ make testapp
cc     testapp.c   -o testapp
$ ./testapp 
04917.240

Note that this answer is conditional on your embedded system having a printf() implementation that is standard-compliant for these details - many embedded environments do not have such an implementation.

A JNI error has occurred, please check your installation and try again in Eclipse x86 Windows 8.1

I have faced the same issue due to packaged name was "Java" after rename package name it was not throwing an error.

Android Preventing Double Click On A Button

final Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {

    private final AtomicBoolean onClickEnabled = new AtomicBoolean(true);

    @Override
    public void onClick(View v) {
        Log.i("TAG", "onClick begin");
        if (!onClickEnabled.compareAndSet(true, false)) {
            Log.i("TAG", "onClick not enabled");
            return;
        }

        button.setEnabled(false);

        // your action here

        button.setEnabled(true);
        onClickEnabled.set(true);
        Log.i("TAG", "onClick end");
    }
});

How do you make a HTTP request with C++?

Here is my minimal wrapper around cURL to be able just to fetch a webpage as a string. This is useful, for example, for unit testing. It is basically a RAII wrapper around the C code.

Install "libcurl" on your machine yum install libcurl libcurl-devel or equivalent.

Usage example:

CURLplusplus client;
string x = client.Get("http://google.com");
string y = client.Get("http://yahoo.com");

Class implementation:

#include <curl/curl.h>


class CURLplusplus
{
private:
    CURL* curl;
    stringstream ss;
    long http_code;
public:
    CURLplusplus()
            : curl(curl_easy_init())
    , http_code(0)
    {

    }
    ~CURLplusplus()
    {
        if (curl) curl_easy_cleanup(curl);
    }
    std::string Get(const std::string& url)
    {
        CURLcode res;
        curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
        curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, this);

        ss.str("");
        http_code = 0;
        res = curl_easy_perform(curl);
        if (res != CURLE_OK)
        {
            throw std::runtime_error(curl_easy_strerror(res));
        }
        curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &http_code);
        return ss.str();
    }
    long GetHttpCode()
    {
        return http_code;
    }
private:
    static size_t write_data(void *buffer, size_t size, size_t nmemb, void *userp)
    {
        return static_cast<CURLplusplus*>(userp)->Write(buffer,size,nmemb);
    }
    size_t Write(void *buffer, size_t size, size_t nmemb)
    {
        ss.write((const char*)buffer,size*nmemb);
        return size*nmemb;
    }
};

Remove numbers from string sql server

Not tested, but you can do something like this:

Create Function dbo.AlphasOnly(@s as varchar(max)) Returns varchar(max) As
Begin
  Declare @Pos int = 1
  Declare @Ret varchar(max) = null
  If @s Is Not Null
  Begin
    Set @Ret = ''
    While @Pos <= Len(@s)
    Begin
      If SubString(@s, @Pos, 1) Like '[A-Za-z]'
      Begin
        Set @Ret = @Ret + SubString(@s, @Pos, 1)
      End
      Set @Pos = @Pos + 1
    End
  End
  Return @Ret
End

The key is to use this as a computed column and index it. It doesn't really matter how fast you make this function if the database has to execute it against every row in your large table every time you run the query.

Python ValueError: too many values to unpack

Iterating over a dictionary object itself actually gives you an iterator over its keys. Python is trying to unpack keys, which you get from m.type + m.purity into (m, k).

My crystal ball says m.type and m.purity are both strings, so your keys are also strings. Strings are iterable, so they can be unpacked; but iterating over the string gives you an iterator over its characters. So whenever m.type + m.purity is more than two characters long, you have too many values to unpack. (And whenever it's shorter, you have too few values to unpack.)

To fix this, you can iterate explicitly over the items of the dict, which are the (key, value) pairs that you seem to be expecting. But if you only want the values, then just use the values.

(In 2.x, itervalues, iterkeys, and iteritems are typically a better idea; the non-iter versions create a new list object containing the values/keys/items. For large dictionaries and trivial tasks within the iteration, this can be a lot slower than the iter versions which just set up an iterator.)

JQUERY: Uncaught Error: Syntax error, unrecognized expression

This can also happen in safari if you try a selector with a missing ], for example

$('select[name="something"')

but interestingly, this same jquery selector with a missing bracket will work in chrome.

How to clear Tkinter Canvas?

Items drawn to the canvas are persistent. create_rectangle returns an item id that you need to keep track of. If you don't remove old items your program will eventually slow down.

From Fredrik Lundh's An Introduction to Tkinter:

Note that items added to the canvas are kept until you remove them. If you want to change the drawing, you can either use methods like coords, itemconfig, and move to modify the items, or use delete to remove them.

AngularJS ng-style with a conditional expression

also this syntax for ternary operator will work:

  ng-style="<$scope.var><condition> ? {
        '<css-prop-1>':((<value>) / (<value2>)*100)+'%',
        '<css-prop-2>':'<string>'
      } : {
        '<css-prop-1>':'<string>',
        '<css-prop-2>':'<string>'
      }"

where <value> are $scope property values. In example:

ng-style="column.histograms.value=>0 ? 
  {
    'width':((column.histograms.value) / (column.histograms.limit)*100)+'%',
    'background':'#F03040'
  } : {
    'width':'1px',
    'background':'#2E92FA'
  }"

```

this allows for some calculaton into the css property values.

Count distinct values

SELECT CUSTOMER, COUNT(*) as PETS 
FROM table_name 
GROUP BY CUSTOMER;

SVG drop shadow using css3

You can easily add a drop-shadow effect to an svg-element using the drop-shadow() CSS function and rgba color values. By using rgba color values you can change the opacity of your shadow.

_x000D_
_x000D_
img.light-shadow{_x000D_
  filter: drop-shadow(0px 3px 3px rgba(0, 0, 0, 0.4));_x000D_
}_x000D_
_x000D_
img.dark-shadow{_x000D_
  filter: drop-shadow(0px 3px 3px rgba(0, 0, 0, 1));_x000D_
}
_x000D_
<img class="light-shadow" src="https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-logo.svg" />_x000D_
<img class="dark-shadow" src="https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-logo.svg" />
_x000D_
_x000D_
_x000D_

Crop image to specified size and picture location

You would need to do something like this. I am typing this off the top of my head, so this may not be 100% correct.

CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); CGContextRef context = CGBitmapContextCreate(NULL, 640, 360, 8, 4 * width, colorSpace, kCGImageAlphaPremultipliedFirst); CGColorSpaceRelease(colorSpace);  CGContextDrawImage(context, CGRectMake(0,-160,640,360), cgImgFromAVCaptureSession);  CGImageRef image = CGBitmapContextCreateImage(context); UIImage* myCroppedImg = [UIImage imageWithCGImage:image]; CGContextRelease(context);       

Getting "unixtime" in Java

Java 8 added a new API for working with dates and times. With Java 8 you can use

import java.time.Instant
...
long unixTimestamp = Instant.now().getEpochSecond();

Instant.now() returns an Instant that represents the current system time. With getEpochSecond() you get the epoch seconds (unix time) from the Instant.

How to enable bulk permission in SQL Server

Try this:

USE master;

GO;
 
GRANT ADMINISTER BULK OPERATIONS TO shira;

How to select Multiple images from UIImagePickerController

You can't use UIImagePickerController, but you can use a custom image picker. I think ELCImagePickerController is the best option, but here are some other libraries you could use:

Objective-C
1. ELCImagePickerController
2. WSAssetPickerController
3. QBImagePickerController
4. ZCImagePickerController
5. CTAssetsPickerController
6. AGImagePickerController
7. UzysAssetsPickerController
8. MWPhotoBrowser
9. TSAssetsPickerController
10. CustomImagePicker
11. InstagramPhotoPicker
12. GMImagePicker
13. DLFPhotosPicker
14. CombinationPickerController
15. AssetPicker
16. BSImagePicker
17. SNImagePicker
18. DoImagePickerController
19. grabKit
20. IQMediaPickerController
21. HySideScrollingImagePicker
22. MultiImageSelector
23. TTImagePicker
24. SelectImages
25. ImageSelectAndSave
26. imagepicker-multi-select
27. MultiSelectImagePickerController
28. YangMingShan(Yahoo like image selector)
29. DBAttachmentPickerController
30. BRImagePicker
31. GLAssetGridViewController
32. CreolePhotoSelection

Swift
1. LimPicker (Similar to WhatsApp's image picker)
2. RMImagePicker
3. DKImagePickerController
4. BSImagePicker
5. Fusuma(Instagram like image selector)
6. YangMingShan(Yahoo like image selector)
7. NohanaImagePicker
8. ImagePicker
9. OpalImagePicker
10. TLPhotoPicker
11. AssetsPickerViewController
12. Alerts-and-pickers/Telegram Picker

Thanx to @androidbloke,
I have added some library that I know for multiple image picker in swift.
Will update list as I find new ones.
Thank You.

C# Encoding a text string with line breaks

Try \n\n , it will work! :)

public async Task AjudaAsync(IDialogContext context, LuisResult result){
await context.PostAsync("How can I help you? \n\n 1.To Schedule \n\n 2.Consult");
context.Wait(MessageReceived);
}

Object of class stdClass could not be converted to string - laravel

$data is indeed an array, but it's made up of objects.

Convert its content to array before creating it:

$data = array();
foreach ($results as $result) {
   $result->filed1 = 'some modification';
   $result->filed2 = 'some modification2';
   $data[] = (array)$result;  
   #or first convert it and then change its properties using 
   #an array syntax, it's up to you
}
Excel::create(....

Codeigniter's `where` and `or_where`

You can change your code to this:

$where_au = "(library.available_until >= '{date('Y-m-d H:i:s)}' OR library.available_until = '00-00-00 00:00:00')";
$this->db
    ->select('*')
    ->from('library')
    ->where('library.rating >=', $form['slider'])
    ->where('library.votes >=', '1000')
    ->where('library.language !=', 'German')
    ->where($where_au)
    ->where('library.release_year >=', $year_start)
    ->where('library.release_year <=', $year_end)
    ->join('rating_repo', 'library.id = rating_repo.id');

Tip: to watch the generated query you can use

echo $this->db->last_query(); die();

sql - insert into multiple tables in one query

Multiple SQL statements must be executed with the mysqli_multi_query() function.

Example (MySQLi Object-oriented):

    <?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
} 

$sql = "INSERT INTO names (firstname, lastname)
VALUES ('inpute value here', 'inpute value here');";
$sql .= "INSERT INTO phones (landphone, mobile)
VALUES ('inpute value here', 'inpute value here');";

if ($conn->multi_query($sql) === TRUE) {
    echo "New records created successfully";
} else {
    echo "Error: " . $sql . "<br>" . $conn->error;
}

$conn->close();
?>

How do I look inside a Python object?

There is a python code library build just for this purpose: inspect Introduced in Python 2.7

currently unable to handle this request HTTP ERROR 500

Your site is serving a 500 Internal Server Error. This can be caused by a number of things, such as:

  • File Permissions
  • Fatal Code Errors
  • Web Server Issues

EDIT

As you have highlighted it is a permission issue. You need to ensure that your files are executable by the web server user

Please see below article for some guidance on proper file permissions. https://www.digitalocean.com/community/questions/proper-permissions-for-web-server-s-directory

C# Listbox Item Double Click Event

I know this question is quite old, but I was looking for a solution to this problem too. The accepted solution is for WinForms not WPF which I think many who come here are looking for.

For anyone looking for a WPF solution, here is a great approach (via Oskar's answer here):

private void myListBox_MouseDoubleClick(object sender, MouseButtonEventArgs e)
{
    DependencyObject obj = (DependencyObject)e.OriginalSource;

    while (obj != null && obj != myListBox)
    {
        if (obj.GetType() == typeof(ListBoxItem))
        {
             // Do something
             break;
         }
         obj = VisualTreeHelper.GetParent(obj);
    }
}

Basically, you walk up the VisualTree until you've either found a parent item that is a ListBoxItem, or you ascend up to the actual ListBox (and therefore did not click a ListBoxItem).

Find TODO tags in Eclipse

Sometimes Window ? Show View does not show the Tasks. Just go to Window ? Show View -> Others and type Tasks in the dialog box.

How to display .svg image using swift

You can add New Symbol Image Set in .xcassets, then you can add SVG file in it

and use it same like image.

enter image description here

Note: This doesn't work on all SVG. You can have a look at the apple documentation

How to link HTML5 form action to Controller ActionResult method in ASP.NET MVC 4

Here I'm basically wrapping a button in a link. The advantage is that you can post to different action methods in the same form.

<a href="Controller/ActionMethod">
    <input type="button" value="Click Me" />
</a>

Adding parameters:

<a href="Controller/ActionMethod?userName=ted">
    <input type="button" value="Click Me" />
</a>

Adding parameters from a non-enumerated Model:

<a href="Controller/[email protected]">
    <input type="button" value="Click Me" />
</a>

You can do the same for an enumerated Model too. You would just have to reference a single entity first. Happy Coding!

Is there any way to change input type="date" format?

i found a way to change format ,its a tricky way, i just changed the appearance of the date input fields using just a CSS code.

_x000D_
_x000D_
input[type="date"]::-webkit-datetime-edit, input[type="date"]::-webkit-inner-spin-button, input[type="date"]::-webkit-clear-button {_x000D_
  color: #fff;_x000D_
  position: relative;_x000D_
}_x000D_
_x000D_
input[type="date"]::-webkit-datetime-edit-year-field{_x000D_
  position: absolute !important;_x000D_
  border-left:1px solid #8c8c8c;_x000D_
  padding: 2px;_x000D_
  color:#000;_x000D_
  left: 56px;_x000D_
}_x000D_
_x000D_
input[type="date"]::-webkit-datetime-edit-month-field{_x000D_
  position: absolute !important;_x000D_
  border-left:1px solid #8c8c8c;_x000D_
  padding: 2px;_x000D_
  color:#000;_x000D_
  left: 26px;_x000D_
}_x000D_
_x000D_
_x000D_
input[type="date"]::-webkit-datetime-edit-day-field{_x000D_
  position: absolute !important;_x000D_
  color:#000;_x000D_
  padding: 2px;_x000D_
  left: 4px;_x000D_
  _x000D_
}
_x000D_
<input type="date" value="2019-12-07">
_x000D_
_x000D_
_x000D_

What does the fpermissive flag do?

A common case for simply setting -fpermissive and not sweating it exists: the thoroughly-tested and working third-party library that won't compile on newer compiler versions without -fpermissive. These libraries exist, and are very likely not the application developer's problem to solve, nor in the developer's schedule budget to do it.

Set -fpermissive and move on in that case.

How to run .sql file in Oracle SQL developer tool to import database?

You could execute the .sql file as a script in the SQL Developer worksheet. Either use the Run Script icon, or simply press F5.

enter image description here

For example,

@path\script.sql;

Remember, you need to put @ as shown above.

But, if you have exported the database using database export utility of SQL Developer, then you should use the Import utility. Follow the steps mentioned here Importing and Exporting using the Oracle SQL Developer 3.0

How to get the directory of the currently running file?

Use package osext

It's providing function ExecutableFolder() that returns an absolute path to folder where the currently running program executable reside (useful for cron jobs). It's cross platform.

Online documentation

package main

import (
    "github.com/kardianos/osext"
    "fmt"
    "log"
)

func main() {
    folderPath, err := osext.ExecutableFolder()
    if err != nil {
        log.Fatal(err)
    }
    fmt.Println(folderPath)
}

async/await - when to return a Task vs void?

The problem with calling async void is that

you don’t even get the task back. You have no way of knowing when the function’s task has completed. —— Crash course in async and await | The Old New Thing

Here are the three ways to call an async function:

async Task<T> SomethingAsync() { ... return t; }
async Task SomethingAsync() { ... }
async void SomethingAsync() { ... }

In all the cases, the function is transformed into a chain of tasks. The difference is what the function returns.

In the first case, the function returns a task that eventually produces the t.

In the second case, the function returns a task which has no product, but you can still await on it to know when it has run to completion.

The third case is the nasty one. The third case is like the second case, except that you don't even get the task back. You have no way of knowing when the function's task has completed.

The async void case is a "fire and forget": You start the task chain, but you don't care about when it's finished. When the function returns, all you know is that everything up to the first await has executed. Everything after the first await will run at some unspecified point in the future that you have no access to.

How to ignore a particular directory or file for tslint?

As an addition

To disable all rules for the next line // tslint:disable-next-line

To disable specific rules for the next line: // tslint:disable-next-line:rule1 rule2...

To disable all rules for the current line: someCode(); // tslint:disable-line

To disable specific rules for the current line: someCode(); // tslint:disable-line:rule1

Linq to Entities join vs groupjoin

According to eduLINQ:

The best way to get to grips with what GroupJoin does is to think of Join. There, the overall idea was that we looked through the "outer" input sequence, found all the matching items from the "inner" sequence (based on a key projection on each sequence) and then yielded pairs of matching elements. GroupJoin is similar, except that instead of yielding pairs of elements, it yields a single result for each "outer" item based on that item and the sequence of matching "inner" items.

The only difference is in return statement:

Join:

var lookup = inner.ToLookup(innerKeySelector, comparer); 
foreach (var outerElement in outer) 
{ 
    var key = outerKeySelector(outerElement); 
    foreach (var innerElement in lookup[key]) 
    { 
        yield return resultSelector(outerElement, innerElement); 
    } 
} 

GroupJoin:

var lookup = inner.ToLookup(innerKeySelector, comparer); 
foreach (var outerElement in outer) 
{ 
    var key = outerKeySelector(outerElement); 
    yield return resultSelector(outerElement, lookup[key]); 
} 

Read more here:

How to iterate over each string in a list of strings and operate on it's elements

The reason is that in your second example i is the word itself, not the index of the word. So

for w1 in words:
     if w1[0] == w1[len(w1) - 1]:
       c += 1
     print c

would the equivalent of your code.

How to add new column to MYSQL table?

Based on your comment it looks like your'e only adding the new column if: mysql_query("SELECT * FROM assessment"); returns false. That's probably not what you wanted. Try removing the '!' on front of $sql in the first 'if' statement. So your code will look like:

$sql=mysql_query("SELECT * FROM assessment");
if ($sql) {
 mysql_query("ALTER TABLE assessment ADD q6 INT(1) NOT NULL AFTER q5");
 echo 'Q6 created'; 
}else...

What is the difference between "expose" and "publish" in Docker?

Most people use docker compose with networks. The documentation states:

The Docker network feature supports creating networks without the need to expose ports within the network, for detailed information see the overview of this feature).

Which means that if you use networks for communication between containers you don't need to worry about exposing ports.

Counting the number of occurences of characters in a string

I don't want to give out the full code. So I want to give you the challenge and have fun with it. I encourage you to make the code simpler and with only 1 loop.

Basically, my idea is to pair up the characters comparison, side by side. For example, compare char 1 with char 2, char 2 with char 3, and so on. When char N not the same with char (N+1) then reset the character count. You can do this in one loop only! While processing this, form a new string. Don't use the same string as your input. That's confusing.

Remember, making things simple counts. Life for developers is hard enough looking at complex code.

Have fun!

Tommy "I should be a Teacher" Kwee

SQL query to find third highest salary in company

We can find the Top nth Salary with this Query.

WITH EMPCTE AS ( SELECT E.*, DENSE_RANK() OVER(ORDER BY SALARY DESC) AS DENSERANK FROM EMPLOYEES E ) SELECT * FROM EMPCTE WHERE DENSERANK=&NUM

Permission denied when launch python script via bash

Do “chmod +x script”

Now try executing

How to generate Javadoc from command line

Link to JavaDoc

I believe this will surely help you.

javadoc -d C:/javadoc/test com.mypackage

Abstract class in Java

An abstract class can not be directly instantiated, but must be derived from to be usable. A class MUST be abstract if it contains abstract methods: either directly

abstract class Foo {
    abstract void someMethod();
}

or indirectly

interface IFoo {
    void someMethod();
}

abstract class Foo2 implements IFoo {
}

However, a class can be abstract without containing abstract methods. Its a way to prevent direct instantation, e.g.

abstract class Foo3 {
}

class Bar extends Foo3 {

}

Foo3 myVar = new Foo3(); // illegal! class is abstract
Foo3 myVar = new Bar(); // allowed!

The latter style of abstract classes may be used to create "interface-like" classes. Unlike interfaces an abstract class is allowed to contain non-abstract methods and instance variables. You can use this to provide some base functionality to extending classes.

Another frequent pattern is to implement the main functionality in the abstract class and define part of the algorithm in an abstract method to be implemented by an extending class. Stupid example:

abstract class Processor {
    protected abstract int[] filterInput(int[] unfiltered);

    public int process(int[] values) {
        int[] filtered = filterInput(values);
        // do something with filtered input
    }
}

class EvenValues extends Processor {
    protected int[] filterInput(int[] unfiltered) {
        // remove odd numbers
    }
}

class OddValues extends Processor {
    protected int[] filterInput(int[] unfiltered) {
        // remove even numbers
    }
}

Display rows with one or more NaN values in pandas dataframe

Suppose gamma1 and gamma2 are two such columns for which df.isnull().any() gives True value , the following code can be used to print the rows.

bool1 = pd.isnull(df['gamma1'])
bool2 = pd.isnull(df['gamma2'])
df[bool1]
df[bool2]

Python speed testing - Time Difference - milliseconds

You could also use:

import time

start = time.clock()
do_something()
end = time.clock()
print "%.2gs" % (end-start)

Or you could use the python profilers.

How to git-svn clone the last n revisions from a Subversion repository?

... 7 years later, in the desert, a tumbleweed blows by ...

I wasn't satisfied with the accepted answer so I created some scripts to do this for you available on Github. These should help anyone who wants to use git svn clone but doesn't want to clone the entire repository and doesn't want to hunt for a specific revision to clone from in the middle of the history (maybe you're cloning a bunch of repos). Here we can just clone the last N revisions:

Use git svn clone to clone the last 50 revisions

# -u    The SVN URL to clone
# -l    The limit of revisions
# -o    The output directory

./git-svn-cloneback.sh -u https://server/project/trunk -l 50 -o myproj --authors-file=svn-authors.txt

Find the previous N revision from an SVN repo

# -u    The SVN URL to clone
# -l    The limit of revisions

./svn-lookback.sh -u https://server/project/trunk -l 5     

Aligning textviews on the left and right edges in Android layout

<TextView
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:text="Hello world" />

<View
    android:layout_width="0dp"
    android:layout_height="match_parent"
    android:layout_weight="1" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Gud bye" />

How to make a <ul> display in a horizontal row

#ul_top_hypers li {
  display: flex;
}

Are dictionaries ordered in Python 3.6+?

Are dictionaries ordered in Python 3.6+?

They are insertion ordered[1]. As of Python 3.6, for the CPython implementation of Python, dictionaries remember the order of items inserted. This is considered an implementation detail in Python 3.6; you need to use OrderedDict if you want insertion ordering that's guaranteed across other implementations of Python (and other ordered behavior[1]).

As of Python 3.7, this is no longer an implementation detail and instead becomes a language feature. From a python-dev message by GvR:

Make it so. "Dict keeps insertion order" is the ruling. Thanks!

This simply means that you can depend on it. Other implementations of Python must also offer an insertion ordered dictionary if they wish to be a conforming implementation of Python 3.7.


How does the Python 3.6 dictionary implementation perform better[2] than the older one while preserving element order?

Essentially, by keeping two arrays.

  • The first array, dk_entries, holds the entries (of type PyDictKeyEntry) for the dictionary in the order that they were inserted. Preserving order is achieved by this being an append only array where new items are always inserted at the end (insertion order).

  • The second, dk_indices, holds the indices for the dk_entries array (that is, values that indicate the position of the corresponding entry in dk_entries). This array acts as the hash table. When a key is hashed it leads to one of the indices stored in dk_indices and the corresponding entry is fetched by indexing dk_entries. Since only indices are kept, the type of this array depends on the overall size of the dictionary (ranging from type int8_t(1 byte) to int32_t/int64_t (4/8 bytes) on 32/64 bit builds)

In the previous implementation, a sparse array of type PyDictKeyEntry and size dk_size had to be allocated; unfortunately, it also resulted in a lot of empty space since that array was not allowed to be more than 2/3 * dk_size full for performance reasons. (and the empty space still had PyDictKeyEntry size!).

This is not the case now since only the required entries are stored (those that have been inserted) and a sparse array of type intX_t (X depending on dict size) 2/3 * dk_sizes full is kept. The empty space changed from type PyDictKeyEntry to intX_t.

So, obviously, creating a sparse array of type PyDictKeyEntry is much more memory demanding than a sparse array for storing ints.

You can see the full conversation on Python-Dev regarding this feature if interested, it is a good read.


In the original proposal made by Raymond Hettinger, a visualization of the data structures used can be seen which captures the gist of the idea.

For example, the dictionary:

d = {'timmy': 'red', 'barry': 'green', 'guido': 'blue'}

is currently stored as [keyhash, key, value]:

entries = [['--', '--', '--'],
           [-8522787127447073495, 'barry', 'green'],
           ['--', '--', '--'],
           ['--', '--', '--'],
           ['--', '--', '--'],
           [-9092791511155847987, 'timmy', 'red'],
           ['--', '--', '--'],
           [-6480567542315338377, 'guido', 'blue']]

Instead, the data should be organized as follows:

indices =  [None, 1, None, None, None, 0, None, 2]
entries =  [[-9092791511155847987, 'timmy', 'red'],
            [-8522787127447073495, 'barry', 'green'],
            [-6480567542315338377, 'guido', 'blue']]

As you can visually now see, in the original proposal, a lot of space is essentially empty to reduce collisions and make look-ups faster. With the new approach, you reduce the memory required by moving the sparseness where it's really required, in the indices.


[1]: I say "insertion ordered" and not "ordered" since, with the existence of OrderedDict, "ordered" suggests further behavior that the dict object doesn't provide. OrderedDicts are reversible, provide order sensitive methods and, mainly, provide an order-sensive equality tests (==, !=). dicts currently don't offer any of those behaviors/methods.


[2]: The new dictionary implementations performs better memory wise by being designed more compactly; that's the main benefit here. Speed wise, the difference isn't so drastic, there's places where the new dict might introduce slight regressions (key-lookups, for example) while in others (iteration and resizing come to mind) a performance boost should be present.

Overall, the performance of the dictionary, especially in real-life situations, improves due to the compactness introduced.

Java code To convert byte to Hexadecimal

If you want a constant-width hex representation, i.e. 0A instead of A, so that you can recover the bytes unambiguously, try format():

StringBuilder result = new StringBuilder();
for (byte bb : byteArray) {
    result.append(String.format("%02X", bb));
}
return result.toString();

How to install SQL Server 2005 Express in Windows 8

I had a different experience loading SQL Server 2005 Express on Windows 8. I was using the installer that already had SP4 applied so maybe that explains the difference. The first error I received was when Setup tried to start the SQL VSS Writer. I just told it to Ignore and it continued. I then ran into the same error Sohail had where the SQL Server service failed to start. There was no point in following the rest of Sohail's method since I already was using a SP4 version of SQLServr.exe and SQLOS.dll. Instead, I just canceled the install rebooted the machine and ran the install again. Everything ran fine the second time around.

The place I found Sohail's technique invaluable was when I needed to install SQL Server 2005 Standard on Windows Server 2012. We have a few new servers we're looking to roll out with Windows 2012 but we didn't feel the need to upgrade SQL Server since the 2005 version has all the functionality we need and the cost to license SQL 2012 on these boxes would have been a 5-figure sum.

I wound up tweaking Sohail's technique a bit by adding steps to revert the SQLServr.exe and SQLOS.dll files so that I could then apply SP4 fully. Below are all the steps I took starting from a scratch install of Windows Server 2012 Standard. I hope this helps anyone else looking to get a fully updated install of SQL Server 2005 x64 on this OS.

  1. Use Server Manger Add roles and features wizard to satisfy all of SQL's prerequisites:
    • Select the Web Server (IIS) Role
    • Add the following additional Web Server Role Services (note that some of these will automatically pull in others, just accept and move on):
      • HTTP Redirection
      • Windows Authentication
      • ASP.NET 3.5 (note that you'll need to tell the wizard to look in the \Sources\SxS folder of the Windows 2012 installation media for this to install properly; just click the link to "Specify an alternate source path" before clicking Install)
      • IIS 6 Metabase Compatibility
      • IIS 6 WMI Compatibility
  2. Start SQL Server 2005 Install, ignoring any compatibility warnings
    • If SQL Server service fails to start during setup, leave dialog up and do the following:
      • Backup SQLServr.exe and SQLOS.dll from C:\Program Files\Microsoft SQL Server\MSSQL.1\MSSQL\Binn
      • Replace those two files from a working copy of SQL Server 2005 that already has had SP4 applied
      • Return to setup, hit Retry and setup will now run to completion.
      • Stop SQL Service and restore orignal versions of SQLServr.exe and SQLOS.dll (or else SP4 doesn't think it is needed in the next step)
  3. Install SQL Server 2005 SP4
  4. Install SQL Server 2005 SP4 Cumulative Hotfix 5069 (Windows Update wasn't offering this for some reason so I had to download and install manually)
  5. If you want the latest documentation, install the latest version of SQL Server 2005 Books Online.

Hide the browse button on a input type=file

Below code is very useful to hide default browse button and use custom instead:

_x000D_
_x000D_
(function($) {_x000D_
  $('input[type="file"]').bind('change', function() {_x000D_
    $("#img_text").html($('input[type="file"]').val());_x000D_
  });_x000D_
})(jQuery)
_x000D_
.file-input-wrapper {_x000D_
  height: 30px;_x000D_
  margin: 2px;_x000D_
  overflow: hidden;_x000D_
  position: relative;_x000D_
  width: 118px;_x000D_
  background-color: #fff;_x000D_
  cursor: pointer;_x000D_
}_x000D_
_x000D_
.file-input-wrapper>input[type="file"] {_x000D_
  font-size: 40px;_x000D_
  position: absolute;_x000D_
  top: 0;_x000D_
  right: 0;_x000D_
  opacity: 0;_x000D_
  cursor: pointer;_x000D_
}_x000D_
_x000D_
.file-input-wrapper>.btn-file-input {_x000D_
  background-color: #494949;_x000D_
  border-radius: 4px;_x000D_
  color: #fff;_x000D_
  display: inline-block;_x000D_
  height: 34px;_x000D_
  margin: 0 0 0 -1px;_x000D_
  padding-left: 0;_x000D_
  width: 121px;_x000D_
  cursor: pointer;_x000D_
}_x000D_
_x000D_
.file-input-wrapper:hover>.btn-file-input {_x000D_
  //background-color: #494949;_x000D_
}_x000D_
_x000D_
#img_text {_x000D_
  float: right;_x000D_
  margin-right: -80px;_x000D_
  margin-top: -14px;_x000D_
}
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
_x000D_
<body>_x000D_
  <div class="file-input-wrapper">_x000D_
    <button class="btn-file-input">SELECT FILES</button>_x000D_
    <input type="file" name="image" id="image" value="" />_x000D_
  </div>_x000D_
  <span id="img_text"></span>_x000D_
</body>
_x000D_
_x000D_
_x000D_

How to Create a script via batch file that will uninstall a program if it was installed on windows 7 64-bit or 32-bit

Assuming you're dealing with Windows 7 x64 and something that was previously installed with some sort of an installer, you can open regedit and search the keys under

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall

(which references 32-bit programs) for part of the name of the program, or

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall

(if it actually was a 64-bit program).

If you find something that matches your program in one of those, the contents of UninstallString in that key usually give you the exact command you are looking for (that you can run in a script).

If you don't find anything relevant in those registry locations, then it may have been "installed" by unzipping a file. Because you mentioned removing it by the Control Panel, I gather this likely isn't then case; if it's in the list of programs there, it should be in one of the registry keys I mentioned.

Then in a .bat script you can do

if exist "c:\program files\whatever\program.exe" (place UninstallString contents here)
if exist "c:\program files (x86)\whatever\program.exe" (place UninstallString contents here)