Programs & Examples On #Teamsite

Create an Array of Arraylists

I totally do not get it, why everyone is suggesting the genric type over the array particularly for this question.

What if my need is to index n different arraylists.

With declaring List<List<Integer>> I need to create n ArrayList<Integer> objects manually or put a for loop to create n lists or some other way, in any way it will always be my duty to create n lists.

Isn't it great if we declare it through casting as List<Integer>[] = (List<Integer>[]) new List<?>[somenumber]. I see it as a good design where one do not have to create all the indexing object (arraylists) by himself

Can anyone enlighten me why this (arrayform) will be a bad design and what are its disadvantages?

Split text with '\r\n'

Following code gives intended results.

string text="some interesting text\nsome text that should be in the same line\r\nsome 
text should be in another line"
var results = text.Split(new[] {"\n","\r\n"}, StringSplitOptions.None);

Instantiating a generic type

You cannot do new T() due to type erasure. The default constructor can only be

public Navigation() {     this("", "", null); } 

​ You can create other constructors to provide default values for trigger and description. You need an concrete object of T.

Http Servlet request lose params from POST body after read it once

I too had the same issue and I believe the code below is more simple and it is working for me,

public class MultiReadHttpServletRequest extends  HttpServletRequestWrapper {

 private String _body;

public MultiReadHttpServletRequest(HttpServletRequest request) throws IOException {
   super(request);
   _body = "";
   BufferedReader bufferedReader = request.getReader();           
   String line;
   while ((line = bufferedReader.readLine()) != null){
       _body += line;
   }
}

@Override
public ServletInputStream getInputStream() throws IOException {
   final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(_body.getBytes());
   return new ServletInputStream() {
       public int read() throws IOException {
           return byteArrayInputStream.read();
       }
   };
}

@Override
public BufferedReader getReader() throws IOException {
   return new BufferedReader(new InputStreamReader(this.getInputStream()));
}
}

in the filter java class,

HttpServletRequest properRequest = ((HttpServletRequest) req);
MultiReadHttpServletRequest wrappedRequest = new MultiReadHttpServletRequest(properRequest);
req = wrappedRequest;
inputJson = IOUtils.toString(req.getReader());
System.out.println("body"+inputJson);

Please let me know if you have any queries

Enable UTF-8 encoding for JavaScript

I too had this issue, I would copy the whole piece of code and put in Notepad, before pasting in Notepad, make sure you save the file type as ALL files and save the doc as utf-8 format. then you can paste your code and run, It should work. ?????? obiviously means unreadable characters.

ssh server connect to host xxx port 22: Connection timed out on linux-ubuntu

Update the security group of that instance. Your local IP must have updated. Every time it’s IP flips. You will have to go update the Security group.

IE8 issue with Twitter Bootstrap 3

From the explanation it says that IE8 is the standard version for you and making content="IE=edge" will render the page in the highest mode. To make it compatible change it to content="IE=8".

IE8 mode supports many established standards, including the W3C Cascading Style Sheets Level 2.1 Specification and the W3C Selectors API; it also provides limited support for the W3C Cascading Style Sheets Level 3 Specification (Working Draft) and other emerging standards.

Edge mode tells Internet Explorer to display content in the highest mode available. With Internet Explorer 9, this is equivalent to IE9 mode. If a future release of Internet Explorer supported a higher compatibility mode, pages set to edge mode would appear in the highest mode supported by that version. Those same pages would still appear in IE9 mode when viewed with Internet Explorer 9.

Reference What does <meta http-equiv="X-UA-Compatible" content="IE=edge"> do?

AngularJS: How can I pass variables between controllers?

The sample above worked like a charm. I just did a modification just in case I need to manage multiple values. I hope this helps!

app.service('sharedProperties', function () {

    var hashtable = {};

    return {
        setValue: function (key, value) {
            hashtable[key] = value;
        },
        getValue: function (key) {
            return hashtable[key];
        }
    }
});

Android Studio: Application Installation Failed

The solution for me was : (in a Huawei)

  • Android Studio -> Build -> Clean Project
  • In the phone -> go to Phone Manager -> Cleanup and Optimize

How to execute mongo commands through shell scripts?

--shell flag can also be used for javascript files

 mongo --shell /path/to/jsfile/test.js 

What does "&" at the end of a linux command mean?

I don’t know for sure but I’m reading a book right now and what I am getting is that a program need to handle its signal ( as when I press CTRL-C). Now a program can use SIG_IGN to ignore all signals or SIG_DFL to restore the default action.

Now if you do $ command & then this process running as background process simply ignores all signals that will occur. For foreground processes these signals are not ignored.

MySQL direct INSERT INTO with WHERE clause

The INSERT INTO Statement
The INSERT INTO statement is used to insert a new row in a table.
SQL INSERT INTO Syntax

It is possible to write the INSERT INTO statement in two forms.

The first form doesn't specify the column names where the data will be inserted, only their values:

INSERT INTO table_name
VALUES (value1, value2, value3,...)

The second form specifies both the column names and the values to be inserted:

INSERT INTO table_name (column1, column2, column3,...)
VALUES (value1, value2, value3,...)

Maven won't run my Project : Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.2.1:exec

For me, the clue was the "org.codehaus.mojo:exec-maven-plugin:1.2.1:exec".
The only place this was referenced was in the "Run project" action under Project Properties=>Actions.

When I changed this action to match the HelloFXMLWithMaven sample project (available in Netbeans 11.1): "clean javafx:run" then executing the Run goal was able to proceed.

Note, I also had to update the pom file's javafx-maven-plugin to also match the sample project but with the mainClass changed for my project.

jQuery window scroll event does not fire up

Nothing seemd to work for me, but this did the trick

$(parent.window.document).scroll(function() {
    alert("bottom!");
});

JDBC connection failed, error: TCP/IP connection to host failed

important:
after any changes or new settings you must restart SQLSERVER service. run services.msc on Windows

How can I change my Cygwin home folder after installation?

Cygwin 1.7.34+

For those using Cygwin 1.7.34 or higher Cygwin supports configuring how to fetch home directory, login shell, and gecos information in /etc/nsswitch.conf. This is detailed in the Cygwin User Guide section:

If you've previously created an /etc/passwd or /etc/group file you'll want to remove those and configure Cygwin using the new Windows Security model to POSIX mappings.

[[ -f /etc/passwd ]] && mv /etc/passwd /etc/passwd.bak
[[ -f /etc/group ]] && mv /etc/group /etc/group.bak

The /etc/nsswitch.conf file's db_home: setting defines how Cygwin fetches the user's home directory. The default setting for db_home: is

db_home: /home/%U

So by default, Cygwin just sets the home dir to /home/$USERNAME. You can change that though to point at any other custom path you want. The supported wildcard characters are:

  • %u The Cygwin username (that's lowercase u).
  • %U The Windows username (that's uppercase U).
  • %D Windows domain in NetBIOS style.
  • %H Windows home directory in POSIX style. Note that, for the db_home: setting, this only makes sense right after the preceeding slash, as in db_home: /%H/cygwin
  • %_ Since space and TAB characters are used to separate the schemata, a space in the filename has to be given as %_ (that's an underscore).
  • %% A per-cent character.

In place of a path, you can specify one of four named path schemata that are predefined.

  1. windows The user's home directory is set to the same directory which is used as Windows home directory, typically something along the lines of %USERPROFILE% or C:\Users\$USERNAME. Of course, the Windows directory is converted to POSIX-style by Cygwin.

  2. cygwin AD only: The user's home directory is set to the POSIX path given in the cygwinHome attribute from the cygwinUser auxiliary class. See also the section called “The cygwin schema”.

  3. unix AD only: The user's home directory is set to the POSIX path given in the unixHomeDirectory attribute from the posixAccount auxiliary class. See also the section called “The unix schema”.

  4. desc The user's home directory is set to the POSIX path given in the home="..." XML-alike setting in the user's description attribute in SAM or AD. See the section called “The desc schema” for a detailed description.

The following will make the user's home directory in Cygwin the same as is used for the Windows home directory.

db_home: windows

Cygwin 1.7.33 or earlier

For those using Cygwin 1.7.33 or earlier, update to the latest version Cygwin and remove previously used /etc/passwd and /etc/group files, then see the steps above.

Else, follow these older steps below.

Firstly, set a Windows environment variable for HOME that points to your user profile:

  1. Open System on the Control Panel
  2. On the Advanced tab click Environment Variables (toward the bottom)
  3. In the User Variables area click "New…"
  4. For Variable name enter HOME
  5. For Variable value enter %USERPROFILE%
  6. Click OK in all the open dialog boxes to apply this new setting

Now we are going to update the Cygwin /etc/passwd file with the Windows %HOME% variable we just created. Shell logins and remote logins via ssh will rely on /etc/passwd to tell them the location of the user's $HOME path.

At the Cygwin bash command prompt type the following:

cp /etc/passwd /etc/passwd.bak
mkpasswd -l -p $(cygpath -H)  > /etc/passwd 
mkpasswd -d -p $(cygpath -H)  >> /etc/passwd 

The -d switch tells mkpasswd to include DOMAIN users, while -l is to only output LOCAL machine users. This is important if you're using a PC at work where the user information is obtained from a Windows Domain Controller.

Now, you can also do the same for groups, though this is not necessary unless you will be using a computer that is part of a Windows Domain. Cygwin reads group information from the Windows account databases, but you can add an /etc/group file if your machine is often disconnected from its Domain Controller.

At the Cygwin bash prompt type the following:

cp /etc/group /etc/group.bak
mkgroup -l > /etc/group 
mkgroup -d >> /etc/group 

Now, exit Cygwin and start it up again. You should find that your HOME path points to the same location as your Windows User Profile -- i.e. /cygdrive/c/Users/username

typeof !== "undefined" vs. != null

if (input == undefined) { ... }

works just fine. It is of course not a null comparison, but I usually find that if I need to distinguish between undefined and null, I actually rather need to distinguish between undefined and just any false value, so

else if (input) { ... }

does it.

If a program redefines undefined it is really braindead anyway.

The only reason I can think of was for IE4 compatibility, it did not understand the undefined keyword (which is not actually a keyword, unfortunately), but of course values could be undefined, so you had to have this:

var undefined;

and the comparison above would work just fine.

In your second example, you probably need double parentheses to make lint happy?

Phonegap Cordova installation Windows

I too struggled a lot with phonegap steps.

The correct documentation is at the following link. http://docs.phonegap.com/en/edge/guide_cli_index.md.html

There is no more cordova command, It is replaced with phonegap.

Compare two Lists for differences

This solution produces a result list, that contains all differences from both input lists. You can compare your objects by any property, in my example it is ID. The only restriction is that the lists should be of the same type:

var DifferencesList = ListA.Where(x => !ListB.Any(x1 => x1.id == x.id))
            .Union(ListB.Where(x => !ListA.Any(x1 => x1.id == x.id)));

How to fix: Error device not found with ADB.exe

I solved:

Just turn off USB debugging and re-enable debugging it immediately

How to make a phone call in android and come back to my activity when the call is done?

@Override
public void onClick(View view) {
    Intent phoneIntent = new Intent(Intent.ACTION_CALL);
    phoneIntent.setData(Uri.parse("tel:91-000-000-0000"));
    if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.CALL_PHONE) != PackageManager.PERMISSION_GRANTED) {
        return;
    }
    startActivity(phoneIntent);
}

Django - after login, redirect user to his custom page --> mysite.com/username

When using Class based views, another option is to use the dispatch method. https://docs.djangoproject.com/en/2.2/ref/class-based-views/base/

Example Code:

Settings.py

LOGIN_URL = 'login'
LOGIN_REDIRECT_URL = 'home'

urls.py

from django.urls import path
from django.contrib.auth import views as auth_views
urlpatterns = [
path('', HomeView.as_view(), name='home'),
path('login/', auth_views.LoginView.as_view(),name='login'),
path('logout/', auth_views.LogoutView.as_view(), name='logout'),
]

views.py

from django.utils.decorators import method_decorator
from django.contrib.auth.decorators import login_required
from django.views.generic import View
from django.shortcuts import redirect

@method_decorator([login_required], name='dispatch')
class HomeView(View):
    model = models.User

    def dispatch(self, request, *args, **kwargs):
        if not request.user.is_authenticated:
            return redirect('login')
        elif some-logic:
            return redirect('some-page') #needs defined as valid url
        return super(HomeView, self).dispatch(request, *args, **kwargs)

Send data from a textbox into Flask?

Declare a Flask endpoint to accept POST input type and then do necessary steps. Use jQuery to post the data.

from flask import request

@app.route('/parse_data', methods=['GET', 'POST'])
def parse_data(data):
    if request.method == "POST":
         #perform action here
var value = $('.textbox').val();
$.ajax({
  type: 'POST',
  url: "{{ url_for('parse_data') }}",
  data: JSON.stringify(value),
  contentType: 'application/json',
  success: function(data){
    // do something with the received data
  }
});

How do you round UP a number in Python?

The syntax may not be as pythonic as one might like, but it is a powerful library.

https://docs.python.org/2/library/decimal.html

from decimal import *
print(int(Decimal(2.3).quantize(Decimal('1.'), rounding=ROUND_UP)))

Timer Interval 1000 != 1 second?

The proper interval to get one second is 1000. The Interval property is the time between ticks in milliseconds:

MSDN: Timer.Interval Property

So, it's not the interval that you set that is wrong. Check the rest of your code for something like changing the interval of the timer, or binding the Tick event multiple times.

Android studio Error "Unsupported Modules Detected: Compilation is not supported for following modules"

In my case I cloned a git-project where both Java and Kotlin included. Then checked another branch and pressed "Sync Project with Gradle Files". Android Studio 3.0.1.

How to use the unsigned Integer in Java 8 and Java 9?

There is no way how to declare an unsigned long or int in Java 8 or Java 9. But some methods treat them as if they were unsigned, for example:

static long values = Long.parseUnsignedLong("123456789012345678");

but this is not declaration of the variable.

How to search for a part of a word with ElasticSearch

Nevermind.

I had to look at the Lucene documentation. Seems I can use wildcards! :-)

curl http://localhost:9200/my_idx/my_type/_search?q=*Doe*

does the trick!

How can I set the color of a selected row in DataGrid

I've tried ControlBrushKey but it didn't work for unselected rows. The background for the unselected row was still white. But I've managed to find out that I have to override the rowstyle.

<DataGrid x:Name="pbSelectionDataGrid" Height="201" Margin="10,0"
          FontSize="20" SelectionMode="Single" FontWeight="Bold">
    <DataGrid.Resources>
        <SolidColorBrush x:Key="{x:Static SystemColors.HighlightBrushKey}" Color="#FFFDD47C"/>
        <SolidColorBrush x:Key="{x:Static SystemColors.ControlBrushKey}" Color="#FFA6E09C"/>
        <SolidColorBrush x:Key="{x:Static SystemColors.HighlightTextBrushKey}" Color="Red"/>
        <SolidColorBrush x:Key="{x:Static SystemColors.ControlTextBrushKey}" Color="Violet"/>
    </DataGrid.Resources>
    <DataGrid.RowStyle>
        <Style TargetType="DataGridRow">
            <Setter Property="Background" Value="LightBlue" />
        </Style>
    </DataGrid.RowStyle>
</DataGrid>

How to update core-js to core-js@3 dependency?

How about reinstalling the node module? Go to the root directory of the project and remove the current node modules and install again.

These are the commands : rm -rf node_modules npm install

OR

npm uninstall -g react-native-cli and

npm install -g react-native-cli

How to use execvp()

In cpp, you need to pay special attention to string types when using execvp:

#include <iostream>
#include <string>
#include <cstring>
#include <stdio.h>
#include <unistd.h>
using namespace std;

const size_t MAX_ARGC = 15; // 1 command + # of arguments
char* argv[MAX_ARGC + 1]; // Needs +1 because of the null terminator at the end
// c_str() converts string to const char*, strdup converts const char* to char*
argv[0] = strdup(command.c_str());

// start filling up the arguments after the first command
size_t arg_i = 1;
while (cin && arg_i < MAX_ARGC) {
    string arg;
    cin >> arg;
    if (arg.empty()) {
        argv[arg_i] = nullptr;
        break;
    } else {
        argv[arg_i] = strdup(arg.c_str());
    }
    ++arg_i;
}

// Run the command with arguments
if (execvp(command.c_str(), argv) == -1) {
    // Print error if command not found
    cerr << "command '" << command << "' not found\n";
}

Reference: execlp?execvp?????

Kill python interpeter in linux from the terminal

pgrep -f youAppFile.py | xargs kill -9

pgrep returns the PID of the specific file will only kill the specific application.

What is the copy-and-swap idiom?

There are some good answers already. I'll focus mainly on what I think they lack - an explanation of the "cons" with the copy-and-swap idiom....

What is the copy-and-swap idiom?

A way of implementing the assignment operator in terms of a swap function:

X& operator=(X rhs)
{
    swap(rhs);
    return *this;
}

The fundamental idea is that:

  • the most error-prone part of assigning to an object is ensuring any resources the new state needs are acquired (e.g. memory, descriptors)

  • that acquisition can be attempted before modifying the current state of the object (i.e. *this) if a copy of the new value is made, which is why rhs is accepted by value (i.e. copied) rather than by reference

  • swapping the state of the local copy rhs and *this is usually relatively easy to do without potential failure/exceptions, given the local copy doesn't need any particular state afterwards (just needs state fit for the destructor to run, much as for an object being moved from in >= C++11)

When should it be used? (Which problems does it solve [/create]?)

  • When you want the assigned-to objected unaffected by an assignment that throws an exception, assuming you have or can write a swap with strong exception guarantee, and ideally one that can't fail/throw..†

  • When you want a clean, easy to understand, robust way to define the assignment operator in terms of (simpler) copy constructor, swap and destructor functions.

    • Self-assignment done as a copy-and-swap avoids oft-overlooked edge cases.‡

  • When any performance penalty or momentarily higher resource usage created by having an extra temporary object during the assignment is not important to your application. ?

swap throwing: it's generally possible to reliably swap data members that the objects track by pointer, but non-pointer data members that don't have a throw-free swap, or for which swapping has to be implemented as X tmp = lhs; lhs = rhs; rhs = tmp; and copy-construction or assignment may throw, still have the potential to fail leaving some data members swapped and others not. This potential applies even to C++03 std::string's as James comments on another answer:

@wilhelmtell: In C++03, there is no mention of exceptions potentially thrown by std::string::swap (which is called by std::swap). In C++0x, std::string::swap is noexcept and must not throw exceptions. – James McNellis Dec 22 '10 at 15:24


‡ assignment operator implementation that seems sane when assigning from a distinct object can easily fail for self-assignment. While it might seem unimaginable that client code would even attempt self-assignment, it can happen relatively easily during algo operations on containers, with x = f(x); code where f is (perhaps only for some #ifdef branches) a macro ala #define f(x) x or a function returning a reference to x, or even (likely inefficient but concise) code like x = c1 ? x * 2 : c2 ? x / 2 : x;). For example:

struct X
{
    T* p_;
    size_t size_;
    X& operator=(const X& rhs)
    {
        delete[] p_;  // OUCH!
        p_ = new T[size_ = rhs.size_];
        std::copy(p_, rhs.p_, rhs.p_ + rhs.size_);
    }
    ...
};

On self-assignment, the above code delete's x.p_;, points p_ at a newly allocated heap region, then attempts to read the uninitialised data therein (Undefined Behaviour), if that doesn't do anything too weird, copy attempts a self-assignment to every just-destructed 'T'!


? The copy-and-swap idiom can introduce inefficiencies or limitations due to the use of an extra temporary (when the operator's parameter is copy-constructed):

struct Client
{
    IP_Address ip_address_;
    int socket_;
    X(const X& rhs)
      : ip_address_(rhs.ip_address_), socket_(connect(rhs.ip_address_))
    { }
};

Here, a hand-written Client::operator= might check if *this is already connected to the same server as rhs (perhaps sending a "reset" code if useful), whereas the copy-and-swap approach would invoke the copy-constructor which would likely be written to open a distinct socket connection then close the original one. Not only could that mean a remote network interaction instead of a simple in-process variable copy, it could run afoul of client or server limits on socket resources or connections. (Of course this class has a pretty horrid interface, but that's another matter ;-P).

Auto insert date and time in form input field?

Javascript won't execute within a value attribute. You could do something like this, though:

<input id="date" name="date">

<script type="text/javascript">
  document.getElementById('date').value = Date();
</script>

You'd probably want to format the date as you prefer, because the default output of Date() looks something like: Tue Jun 16 2009 10:47:10 GMT-0400 (Eastern Daylight Time). See this SO question for info about formatting a date.

Can't find bundle for base name

When you create an initialization of the ResourceBundle, you can do this way also.

For testing and development I have created a properties file under \src with the name prp.properties.

Use this way:

ResourceBundle rb = ResourceBundle.getBundle("prp");

Naming convention and stuff:

http://192.9.162.55/developer/technicalArticles/Intl/ResourceBundles/

Cross-Origin Read Blocking (CORB)

It seems that this warning occured when sending an empty response with a 200.

This configuration in my .htaccess display the warning on Chrome:

Header always set Access-Control-Allow-Origin "*"
Header always set Access-Control-Allow-Methods "POST,GET,HEAD,OPTIONS,PUT,DELETE"
Header always set Access-Control-Allow-Headers "Access-Control-Allow-Headers, Origin,Accept, X-Requested-With, Content-Type, Access-Control-Request-Method, Access-Control-Request-Headers, Authorization"

RewriteEngine On
RewriteCond %{REQUEST_METHOD} OPTIONS
RewriteRule .* / [R=200,L]

But changing the last line to

RewriteRule .* / [R=204,L]

resolve the issue!

SQL - How to find the highest number in a column?

If you've just inserted a record into the Customers table and you need the value of the recently populated ID field, you can use the SCOPE_IDENTITY function. This is only useful when the INSERT has occurred within the same scope as the call to SCOPE_IDENTITY.

INSERT INTO Customers(ID, FirstName, LastName)
Values
(23, 'Bob', 'Smith')

SET @mostRecentId = SCOPE_IDENTITY()

This may or may not be useful for you, but it's a good technique to be aware of. It will also work with auto-generated columns.

Genymotion Android emulator - adb access?

My working solution is:

cd /opt/genymobile/genymotion/tools
./adb shell

You have to use its own adb tool.

How to create table using select query in SQL Server?

select <column list> into <dest. table> from <source table>;

You could do this way.

SELECT windows_release, windows_service_pack_level, 
       windows_sku, os_language_version
into   new_table_name
FROM   sys.dm_os_windows_info OPTION (RECOMPILE);

OSX El Capitan: sudo pip install OSError: [Errno: 1] Operation not permitted

pip install --ignore-installed six

This will do the job, then you can try your first command.

Via http://github.com/pypa/pip/issues/3165

How to add onload event to a div element

You can attach an event listener as below. It will trigger whenever the div having selector #my-id loads completely to DOM.

$(document).on('EventName', '#my-id', function() {
 // do something
});

Inthis case EventName may be 'load' or 'click'

https://api.jquery.com/on/#on-events-selector-data-handler

Sort Java Collection

Use sort.

You just have to do this:

All elements in the list must implement the Comparable interface.

(Or use the version below it, as others already said.)

How to get AM/PM from a datetime in PHP

Perfect answer for AM/PM live time solution

<?php echo date('h:i A', time())?>

How to access site through IP address when website is on a shared host?

Include the port number with the IP address.

For example:

http://19.18.20.101:5566

where 5566 is the port number.

Removing the fragment identifier from AngularJS urls (# symbol)

According to the documentation. You can use:

$locationProvider.html5Mode(true).hashPrefix('!');

NB: If your browser does not support to HTML 5. Dont worry :D it have fallback to hashbang mode. So, you don't need to check with if(window.history && window.history.pushState){ ... } manually

For example: If you click: <a href="/other">Some URL</a>

In HTML5 Browser: angular will automatically redirect to example.com/other

In Not HTML5 Browser: angular will automatically redirect to example.com/#!/other

Prevent redirect after form is submitted

The design of HTTP means that making a POST with data will return a page. The original designers probably intended for that to be a "result" page of your POST.

It is normal for a PHP application to POST back to the same page as it can not only process the POST request, but it can generate an updated page based on the original GET but with the new information from the POST. However, there's nothing stopping your server code from providing completely different output. Alternatively, you could POST to an entirely different page.

If you don't want the output, one method that I've seen before AJAX took off was for the server to return a HTTP response code of (I think) 250. This is called "No Content" and this should make the browser ignore the data.

Of course, the third method is to make an AJAX call with your submitted data, instead.

How to generate Entity Relationship (ER) Diagram of a database using Microsoft SQL Server Management Studio?

  1. Go to Sql Server Management Studio >
  2. Object Explorer >
  3. Databases >
  4. Choose and expand your Database.
  5. Under your database right click on "Database Diagrams" and select "New Database Diagram".
  6. It will a open a new window. Choose tables to include in ER-Diagram (to select multiple tables press "ctrl" or "shift" button and select tables).
  7. Click add.
  8. Wait for it to complete. Done!

You can save generated diagram for future use.

screenshot

Creating a simple XML file using python

These days, the most popular (and very simple) option is the ElementTree API, which has been included in the standard library since Python 2.5.

The available options for that are:

  • ElementTree (Basic, pure-Python implementation of ElementTree. Part of the standard library since 2.5)
  • cElementTree (Optimized C implementation of ElementTree. Also offered in the standard library since 2.5)
  • LXML (Based on libxml2. Offers a rich superset of the ElementTree API as well XPath, CSS Selectors, and more)

Here's an example of how to generate your example document using the in-stdlib cElementTree:

import xml.etree.cElementTree as ET

root = ET.Element("root")
doc = ET.SubElement(root, "doc")

ET.SubElement(doc, "field1", name="blah").text = "some value1"
ET.SubElement(doc, "field2", name="asdfasd").text = "some vlaue2"

tree = ET.ElementTree(root)
tree.write("filename.xml")

I've tested it and it works, but I'm assuming whitespace isn't significant. If you need "prettyprint" indentation, let me know and I'll look up how to do that. (It may be an LXML-specific option. I don't use the stdlib implementation much)

For further reading, here are some useful links:

As a final note, either cElementTree or LXML should be fast enough for all your needs (both are optimized C code), but in the event you're in a situation where you need to squeeze out every last bit of performance, the benchmarks on the LXML site indicate that:

  • LXML clearly wins for serializing (generating) XML
  • As a side-effect of implementing proper parent traversal, LXML is a bit slower than cElementTree for parsing.

How to unzip a file in Powershell?

In PowerShell v5+, there is an Expand-Archive command (as well as Compress-Archive) built in:

Expand-Archive c:\a.zip -DestinationPath c:\a

Get image dimensions

<?php 
    list($width, $height) = getimagesize("http://site.com/image.png"); 
    $arr = array('h' => $height, 'w' => $width );
?>

What's the difference between 'git merge' and 'git rebase'?

For easy understand can see my figure.

Rebase will change commit hash, so that if you want to avoid much of conflict, just use rebase when that branch is done/complete as stable.

enter image description here

Using LIKE in an Oracle IN clause

I prefer this

WHERE CASE WHEN my_col LIKE '%val1%' THEN 1    
           WHEN my_col LIKE '%val2%' THEN 1
           WHEN my_col LIKE '%val3%' THEN 1
           ELSE 0
           END = 1

I'm not saying it's optimal but it works and it's easily understood. Most of my queries are adhoc used once so performance is generally not an issue for me.

Passing string parameter in JavaScript function

You can pass string parameters to JavaScript functions like below code:

I passed three parameters where the third one is a string parameter.

var btn ="<input type='button' onclick='RoomIsReadyFunc(" + ID + "," + RefId + ",\"" + YourString + "\");'  value='Room is Ready' />";

// Your JavaScript function

function RoomIsReadyFunc(ID, RefId, YourString)
{
    alert(ID);
    alert(RefId);
    alert(YourString);
}

Syntax error on print with Python 3

Because in Python 3, print statement has been replaced with a print() function, with keyword arguments to replace most of the special syntax of the old print statement. So you have to write it as

print("Hello World")

But if you write this in a program and someone using Python 2.x tries to run it, they will get an error. To avoid this, it is a good practice to import print function:

from __future__ import print_function

Now your code works on both 2.x & 3.x.

Check out below examples also to get familiar with print() function.

Old: print "The answer is", 2*2
New: print("The answer is", 2*2)

Old: print x,           # Trailing comma suppresses newline
New: print(x, end=" ")  # Appends a space instead of a newline

Old: print              # Prints a newline
New: print()            # You must call the function!

Old: print >>sys.stderr, "fatal error"
New: print("fatal error", file=sys.stderr)

Old: print (x, y)       # prints repr((x, y))
New: print((x, y))      # Not the same as print(x, y)!

Source: What’s New In Python 3.0?

How to initialize an array in angular2 and typescript

In order to make more concise you can declare constructor parameters as public which automatically create properties with same names and these properties are available via this:

export class Environment {

  constructor(public id:number, public name:string) {}

  getProperties() {
    return `${this.id} : ${this.name}`;
  }
}

let serverEnv = new Environment(80, 'port');
console.log(serverEnv);

 ---result---
// Environment { id: 80, name: 'port' }

Oracle PL/SQL : remove "space characters" from a string

To replace one or more white space characters by a single blank you should use {2,} instead of *, otherwise you would insert a blank between all non-blank characters.

REGEXP_REPLACE( my_value, '[[:space:]]{2,}', ' ' )

How can I use JQuery to post JSON data?

Using Promise and checking if the body object is a valid JSON. If not a Promise reject will be returned.

var DoPost = function(url, body) {
    try {
        body = JSON.stringify(body);
    } catch (error) {
        return reject(error);
    }
    return new Promise((resolve, reject) => {
        $.ajax({
                type: 'POST',
                url: url,
                data: body,
                contentType: "application/json",
                dataType: 'json'
            })
            .done(function(data) {
                return resolve(data);
            })
            .fail(function(error) {
                console.error(error);
                return reject(error);
            })
            .always(function() {
                // called after done or fail
            });
    });
}

How can we redirect a Java program console output to multiple files?

To solve the problem I use ${string_prompt} variable. It shows a input dialog when application runs. I can set the date/time manually at that dialog.

  1. Move cursor at the end of file path. enter image description here

  2. Click variables and select string_prompt enter image description here

  3. Select Apply and Run enter image description here enter image description here

Subtract minute from DateTime in SQL Server 2005

I spent a while trying to do the same thing, trying to subtract the hours:minutes from datetime - here's how I did it:

convert( varchar, cast((RouteMileage / @average_speed) as integer))+ ':' +  convert( varchar, cast((((RouteMileage / @average_speed) - cast((RouteMileage / @average_speed) as integer)) * 60) as integer)) As TravelTime,

dateadd( n, -60 * CAST( (RouteMileage / @average_speed) AS DECIMAL(7,2)), @entry_date) As DepartureTime 

OUTPUT:

DeliveryDate                TravelTime             DepartureTime
2012-06-02 12:00:00.000       25:49         2012-06-01 10:11:00.000

How do I make this file.sh executable via double click?

You can just tell Finder to open the .sh file in Terminal:

  1. Select the file
  2. Get Info (cmd-i) on it
  3. In the "Open with" section, choose "Other…" in the popup menu
  4. Choose Terminal as the application

This will have the exact same effect as renaming it to .command except… you don't have to rename it :)

Exporting to .xlsx using Microsoft.Office.Interop.Excel SaveAs Error

This is how you save the relevant file as a Excel12 (.xlsx) file... It is not as you would intuitively think i.e. using Excel.XlFileFormat.xlExcel12 but Excel.XlFileFormat.xlOpenXMLWorkbook. The actual C# command was

excelWorkbook.SaveAs(strFullFilePathNoExt, Excel.XlFileFormat.xlOpenXMLWorkbook, Missing.Value,
    Missing.Value, false, false, Excel.XlSaveAsAccessMode.xlNoChange, 
    Excel.XlSaveConflictResolution.xlUserResolution, true, 
    Missing.Value, Missing.Value, Missing.Value);

I hope this helps someone else in the future.


Missing.Value is found in the System.Reflection namespace.

How do I exit the Vim editor?

Pictures are worth a thousand Unix commands and options:

Enter image description here

I draw this to my students each semester and they seem to grasp vi afterwards.

vi is a finite state machine with only three states.

Upon starting, vi goes into COMMAND mode, where you can type short, few character commands, blindly. You know what you are doing; this isn't for amateurs.

When you want to actually edit text, you should go to INSERT mode with some one-character command:

  • i: go to INSERT in the place of the cursor
  • I: go to INSERT mode at the beginning of the line
  • a: append after the cursor
  • A: append at the end of line
  • o: open a new line below the current line
  • O: open a new line in the place of the current line

Now, answering the question: exiting.

You can exit vi from EX mode:

  • q: if you haven't made any modifications, or saved them beforehand
  • q!: ignores any modifications and quit
  • wq: save and quit
  • x: this is equal to wq

w and x accept a file name parameter. If you started vi with a filename, you need not give it here again.

At last, the most important: how can you reach EX mode?

EX mode is for long commands that you can see typing at the bottom line of the screen. From COMMAND mode, you push colon, :, and a colon will appear at the bottom line, where you can type the above commands.

From INSERT mode, you need to push ESC, i.e. the Escape button, going to COMMAND mode, and then : to go to EX mode.

If you are unsure, push ESC and that will bring you to command mode.

So, the robust method is ESC-:-x-Enter which saves your file and quits.

How do you close/hide the Android soft keyboard using Java?

I use Kotlin extensions for showing and hiding the Keyboard.

fun View.showKeyboard() {
  this.requestFocus()
  val inputMethodManager = context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
  inputMethodManager.showSoftInput(this, InputMethodManager.SHOW_IMPLICIT)
}

fun View.hideKeyboard() {
  val inputMethodManager = context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
  inputMethodManager.hideSoftInputFromWindow(windowToken, 0)
}

Removing Java 8 JDK from Mac

You just need to use these commands

sudo rm -rf /Library/Java/*
sudo rm -rf /Library/PreferencePanes/Java*
sudo rm -rf /Library/Internet\ Plug-Ins/Java*

Set line spacing

I am not sure if this is what you meant:

line-height: size;

Write-back vs Write-Through caching?

Write-back and write-through describe policies when a write hit occurs, that is when the cache has the requested information. In these examples, we assume a single processor is writing to main memory with a cache.

Write-through: The information is written to the cache and memory, and the write finishes when both have finished. This has the advantage of being simpler to implement, and the main memory is always consistent (in sync) with the cache (for the uniprocessor case - if some other device modifies main memory, then this policy is not enough), and a read miss never results in writes to main memory. The obvious disadvantage is that every write hit has to do two writes, one of which accesses slower main memory.

Write-back: The information is written to a block in the cache. The modified cache block is only written to memory when it is replaced (in effect, a lazy write). A special bit for each cache block, the dirty bit, marks whether or not the cache block has been modified while in the cache. If the dirty bit is not set, the cache block is "clean" and a write miss does not have to write the block to memory.

The advantage is that writes can occur at the speed of the cache, and if writing within the same block only one write to main memory is needed (when the previous block is being replaced). The disadvantages are that this protocol is harder to implement, main memory can be not consistent (not in sync) with the cache, and reads that result in replacement may cause writes of dirty blocks to main memory.

The policies for a write miss are detailed in my first link.

These protocols don't take care of the cases with multiple processors and multiple caches, as is common in modern processors. For this, more complicated cache coherence mechanisms are required. Write-through caches have simpler protocols since a write to the cache is immediately reflected in memory.

Good resources:

Python convert tuple to string

Use str.join:

>>> tup = ('a', 'b', 'c', 'd', 'g', 'x', 'r', 'e')
>>> ''.join(tup)
'abcdgxre'
>>>
>>> help(str.join)
Help on method_descriptor:

join(...)
    S.join(iterable) -> str

    Return a string which is the concatenation of the strings in the
    iterable.  The separator between elements is S.

>>>

how to move elasticsearch data from one server to another

If you don't want to use the elasticdump like a console tool. You can use next node.js script

How do I get a PHP class constructor to call its parent's parent's constructor?

class Grandpa 
{
    public function __construct()
    {}
}

class Papa extends Grandpa
{
    public function __construct()
    {
        //call Grandpa's constructor
        parent::__construct();
    }
}

class Kiddo extends Papa
{
    public function __construct()
    {
        //this is not a bug, it works that way in php
        Grandpa::__construct();
    }
}

Forward request headers from nginx proxy server

If you want to pass the variable to your proxy backend, you have to set it with the proxy module.

location / {
    proxy_pass                      http://example.com;
    proxy_set_header                Host example.com;
    proxy_set_header                HTTP_Country-Code $geoip_country_code;
    proxy_pass_request_headers      on;
}

And now it's passed to the proxy backend.

How to upload images into MySQL database using PHP code

This is the perfect code for uploading and displaying image through MySQL database.

<html>
<body>
<form method="post" enctype="multipart/form-data">
<input type="file" name="image"/>
<input type="submit" name="submit" value="Upload"/>
</form>
<?php
    if(isset($_POST['submit']))
    {
     if(getimagesize($_FILES['image']['tmp_name'])==FALSE)
     {
        echo " error ";
     }
     else
     {
        $image = $_FILES['image']['tmp_name'];
        $image = addslashes(file_get_contents($image));
        saveimage($image);
     }
    }
    function saveimage($image)
    {
        $dbcon=mysqli_connect('localhost','root','','dbname');
        $qry="insert into tablename (name) values ('$image')";
        $result=mysqli_query($dbcon,$qry);
        if($result)
        {
            echo " <br/>Image uploaded.";
            header('location:urlofpage.php');
        }
        else
        {
            echo " error ";
        }
    }
?>
</body>
</html>

nodeJS - How to create and read session with express

I forgot to tell a bug when i use I use req.session.email = req.param('email'), the server error says cannot sett property email of undefined.

The reason of this error is a wrong order of app.use. You must configure express in this order:

app.use(express.cookieParser());
app.use(express.session({ secret: sessionVal }));
app.use(app.route);

NameError: global name 'xrange' is not defined in Python 3

I agree with the last answer.But there is another way to solve this problem.You can download the package named future,such as pip install future.And in your .py file input this "from past.builtins import xrange".This method is for the situation that there are many xranges in your file.

Converting pixels to dp

like this:

public class ScreenUtils {

    public static float dpToPx(Context context, float dp) {
        if (context == null) {
            return -1;
        }
        return dp * context.getResources().getDisplayMetrics().density;
    }

    public static float pxToDp(Context context, float px) {
        if (context == null) {
            return -1;
        }
        return px / context.getResources().getDisplayMetrics().density;
    }
}

dependent on Context, return float value, static method

from: https://github.com/Trinea/android-common/blob/master/src/cn/trinea/android/common/util/ScreenUtils.java#L15

Simple way to read single record from MySQL

The easiest way is to use mysql_result. I copied some of the code below from other answers to save time.

$link = mysql_connect('localhost','root','yourPassword')
mysql_select_db('database',$link);
$sql = 'SELECT id FROM games'
$result = mysql_query($sql,$link);

$num_rows = mysql_num_rows($result);

// i is the row number and will be 0 through $num_rows-1
for ($i = 0; $i < $num_rows; $i++) {
    $value = mysql_result($result, i, 'id');
    echo 'Row ', i, ': ', $value, "\n";
}

curl: (60) SSL certificate problem: unable to get local issuer certificate

Relating to 'SSL certificate problem: unable to get local issuer certificate' error. It is important to note that this applies to the system sending the CURL request, and NOT the server receiving the request.

  1. Download the latest cacert.pem from https://curl.haxx.se/ca/cacert.pem

  2. Add the following line to php.ini: (if this is shared hosting and you don't have access to php.ini then you could add this to .user.ini in public_html).

    curl.cainfo="/path/to/downloaded/cacert.pem"

    Make sure you enclose the path within double quotation marks!!!

  3. By default, the FastCGI process will parse new files every 300 seconds (if required you can change the frequency by adding a couple of files as suggested here https://ss88.uk/blog/fast-cgi-and-user-ini-files-the-new-htaccess/).

Difference between scaling horizontally and vertically for databases

SQL databases like Oracle, db2 also support Horizontal scaling through Shared disk cluster. For example Oracle RAC, IBM DB2 purescale or Sybase ASE Cluster edition. New node can be added to Oracle RAC system or DB2 purescale system to achieve horizontal scaling.

But the approach is different from noSQL databases (like mongodb, CouchDB or IBM Cloudant) is that the data sharding is not part of Horizontal scaling. In noSQL databases data is shraded during horizontal scaling.

How to Make A Chevron Arrow Using CSS?

Just use before and after Pseudo-elements - CSS

_x000D_
_x000D_
*{box-sizing: border-box; padding: 0; margin: 0}_x000D_
:root{background: white; transition: background .3s ease-in-out}_x000D_
:root:hover{background: red }_x000D_
div{_x000D_
  margin: 20px auto;_x000D_
  width: 150px;_x000D_
  height: 150px;_x000D_
  position:relative_x000D_
}_x000D_
_x000D_
div:before, div:after{_x000D_
  content: '';_x000D_
  position: absolute;_x000D_
  width: 75px;_x000D_
  height: 20px;_x000D_
  background: black;_x000D_
  left: 40px_x000D_
}_x000D_
_x000D_
div:before{_x000D_
  top: 45px;_x000D_
  transform: rotateZ(45deg)_x000D_
}_x000D_
_x000D_
div:after{_x000D_
  bottom: 45px;_x000D_
  transform: rotateZ(-45deg)_x000D_
}
_x000D_
<div/>
_x000D_
_x000D_
_x000D_

How can I write maven build to add resources to classpath?

A cleaner alternative of putting your config file into a subfolder of src/main/resources would be to enhance your classpath locations. This is extremely easy to do with Maven.

For instance, place your property file in a new folder src/main/config, and add the following to your pom:

 <build>
    <resources>
        <resource>
            <directory>src/main/config</directory>
        </resource>
    </resources>
 </build>

From now, every files files under src/main/config is considered as part of your classpath (note that you can exclude some of them from the final jar if needed: just add in the build section:

    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-jar-plugin</artifactId>
            <configuration>
                <excludes>
                    <exclude>my-config.properties</exclude>
                </excludes>
            </configuration>
        </plugin>
    </plugins>

so that my-config.properties can be found in your classpath when you run your app from your IDE, but will remain external from your jar in your final distribution).

How to create PDFs in an Android app?

It's not easy to find a full solution of the problem of a convertion of an arbitrary HTML to PDF with non-english letters in Android. I test it for russian unicode letters.

We use three libraries:

(1) Jsoup (jsoup-1.7.3.jar) for a convertion from HTML to XHTML,

(2) iTextPDF (itextpdf-5.5.0.jar),

(3) XMLWorker (xmlworker-5.5.1.jar).

public boolean createPDF(String rawHTML, String fileName, ContextWrapper context){
    final String APPLICATION_PACKAGE_NAME = context.getBaseContext().getPackageName();
    File path = new File( Environment.getExternalStorageDirectory(), APPLICATION_PACKAGE_NAME );
    if ( !path.exists() ){ path.mkdir(); }
    File file = new File(path, fileName);

    try{

    Document document = new Document();
    PdfWriter writer = PdfWriter.getInstance(document, new FileOutputStream(file));
    document.open();

    // ?????????????? HTML
    String htmlText = Jsoup.clean( rawHTML, Whitelist.relaxed() );
    InputStream inputStream = new ByteArrayInputStream( htmlText.getBytes() );

    // ???????? ???????? PDF
    XMLWorkerHelper.getInstance().parseXHtml(writer, document,
        inputStream, null, Charset.defaultCharset(), new MyFont());

    document.close();
    return true;

    } catch (FileNotFoundException e) {
        e.printStackTrace();
        return false;
    } catch (DocumentException e) {
        e.printStackTrace();
        return false;
    } catch (IOException e) {
        e.printStackTrace();
        return false;
    } 

The difficult problem is to display russian letters in PDF by using iTextPDF XMLWorker library. For this we should create our own implementation of FontProvider interface:

public class MyFont implements FontProvider{
    private static final String FONT_PATH = "/system/fonts/DroidSans.ttf";
    private static final String FONT_ALIAS = "my_font";

    public MyFont(){ FontFactory.register(FONT_PATH, FONT_ALIAS); }

    @Override
    public Font getFont(String fontname, String encoding, boolean embedded,
        float size, int style, BaseColor color){

        return FontFactory.getFont(FONT_ALIAS, BaseFont.IDENTITY_H, 
            BaseFont.EMBEDDED, size, style, color);
    }

    @Override
    public boolean isRegistered(String name) { return name.equals( FONT_ALIAS ); }
}

Here we use the standard Android font Droid Sans, which is located in the system folder:

private static final String FONT_PATH = "/system/fonts/DroidSans.ttf";

Can I force pip to reinstall the current version?

pip install --upgrade --force-reinstall <package>

When upgrading, reinstall all packages even if they are already up-to-date.

pip install -I <package>
pip install --ignore-installed <package>

Ignore the installed packages (reinstalling instead).

return error message with actionResult

Inside Controller Action you can access HttpContext.Response. There you can set the response status as in the following listing.

[HttpPost]
public ActionResult PostViaAjax()
{
    var body = Request.BinaryRead(Request.TotalBytes);

    var result = Content(JsonError(new Dictionary<string, string>()
    {
        {"err", "Some error!"}
    }), "application/json; charset=utf-8");
    HttpContext.Response.StatusCode = (int)HttpStatusCode.BadRequest;
    return result;
}

How to prevent favicon.ico requests?

You could use

<link rel="shortcut icon" href="http://localhost/" />

That way it won't actually be requested from the server.

What is the difference between instanceof and Class.isAssignableFrom(...)?

A more direct equivalent to a instanceof B is

B.class.isInstance(a)

This works (returns false) when a is null too.

Is it possible to set a number to NaN or infinity?

Yes, you can use numpy for that.

import numpy as np
a = arange(3,dtype=float)

a[0] = np.nan
a[1] = np.inf
a[2] = -np.inf

a # is now [nan,inf,-inf]

np.isnan(a[0]) # True
np.isinf(a[1]) # True
np.isinf(a[2]) # True

Generate JSON string from NSDictionary in iOS

You can also do this on-the-fly by entering the following into the debugger

po [[NSString alloc] initWithData:[NSJSONSerialization dataWithJSONObject:yourDictionary options:1 error:nil] encoding:4];

Python SQLite: database is locked

I had the same problem: sqlite3.IntegrityError

As mentioned in many answers, the problem is that a connection has not been properly closed.

In my case I had try except blocks. I was accessing the database in the try block and when an exception was raised I wanted to do something else in the except block.

try:
    conn = sqlite3.connect(path)
    cur = conn.cursor()
    cur.execute('''INSERT INTO ...''')
except:
    conn = sqlite3.connect(path)
    cur = conn.cursor()
    cur.execute('''DELETE FROM ...''')
    cur.execute('''INSERT INTO ...''')

However, when the exception was being raised the connection from the try block had not been closed.

I solved it using with statements inside the blocks.

try:
    with sqlite3.connect(path) as conn:
        cur = conn.cursor()
        cur.execute('''INSERT INTO ...''')
except:
    with sqlite3.connect(path) as conn:
        cur = conn.cursor()
        cur.execute('''DELETE FROM ...''')
        cur.execute('''INSERT INTO ...''')

How to avoid the "divide by zero" error in SQL?

EDIT: I'm getting a lot of downvotes on this recently...so I thought I'd just add a note that this answer was written before the question underwent it's most recent edit, where returning null was highlighted as an option...which seems very acceptable. Some of my answer was addressed to concerns like that of Edwardo, in the comments, who seemed to be advocating returning a 0. This is the case I was railing against.

ANSWER: I think there's an underlying issue here, which is that division by 0 is not legal. It's an indication that something is fundementally wrong. If you're dividing by zero, you're trying to do something that doesn't make sense mathematically, so no numeric answer you can get will be valid. (Use of null in this case is reasonable, as it is not a value that will be used in later mathematical calculations).

So Edwardo asks in the comments "what if the user puts in a 0?", and he advocates that it should be okay to get a 0 in return. If the user puts zero in the amount, and you want 0 returned when they do that, then you should put in code at the business rules level to catch that value and return 0...not have some special case where division by 0 = 0.

That's a subtle difference, but it's important...because the next time someone calls your function and expects it to do the right thing, and it does something funky that isn't mathematically correct, but just handles the particular edge case it's got a good chance of biting someone later. You're not really dividing by 0...you're just returning an bad answer to a bad question.

Imagine I'm coding something, and I screw it up. I should be reading in a radiation measurement scaling value, but in a strange edge case I didn't anticipate, I read in 0. I then drop my value into your function...you return me a 0! Hurray, no radiation! Except it's really there and it's just that I was passing in a bad value...but I have no idea. I want division to throw the error because it's the flag that something is wrong.

Could not load file or assembly "Oracle.DataAccess" or one of its dependencies

I found the solution with following steps:

  • remove the Oracle.DataAcces.dll reference,
    and add a fresh reference to:
    C:\windows\assembly\GAC\Oracle.DataAccess\X.XXX.X.XX__89b483f429c47342/oracle.dataaccess.dll
  • Make local copy= false.

Hope it helps

TypeError: 'module' object is not callable

Assume that the content of YourClass.py is:

class YourClass:
    # ......

If you use:

from YourClassParentDir import YourClass  # means YourClass.py

In this way, I got TypeError: 'module' object is not callable if you then tried to use YourClass().

But, if you use:

from YourClassParentDir.YourClass import YourClass   # means Class YourClass

or use YourClass.YourClass(), it works for me.

Handling Enter Key in Vue.js

You can also pass events down into child components with something like this:

<CustomComponent
    @keyup.enter="handleKeyUp"
/>

...

<template>
    <div>
        <input
            type="text"
            v-on="$listeners"
        >
    </div>
</template>

<script>
export default {
    name: 'CustomComponent',

    mounted() {
        console.log('listeners', this.$listeners)
    },
}
</script>

That works well if you have a pass-through component and want the listeners to go onto a specific element.

How can I make my custom objects Parcelable?

Android parcable has some unique things. Those are given bellow:

  1. You have to read Parcel as the same order where you put data on parcel.
  2. Parcel will empty after read from parcel. That is if you have 3 data on your parcel. Then after read 3 times parcel will be empty.

Example: To make a class Parceble it must be implement Parceble. Percable has 2 method:

int describeContents();
void writeToParcel(Parcel var1, int var2);

Suppose you have a Person class and it has 3 field, firstName,lastName and age. After implementing Parceble interface. this interface is given bellow:

import android.os.Parcel;
import android.os.Parcelable;
public class Person implements Parcelable{
    private String firstName;
    private String lastName;
    private int age;

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public int getAge() {
        return age;
    }

    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel parcel, int i) {
        parcel.writeString(firstName);
        parcel.writeString(lastName);
        parcel.writeInt(age);
    }

}

Here writeToParcel method we are writing/adding data on Parcel in an order. After this we have to add bellow code for reading data from parcel:

protected Person(Parcel in) {
        firstName = in.readString();
        lastName = in.readString();
        age = in.readInt();
    }

    public static final Creator<Person> CREATOR = new Creator<Person>() {
        @Override
        public Person createFromParcel(Parcel in) {
            return new Person(in);
        }

        @Override
        public Person[] newArray(int size) {
            return new Person[size];
        }
    };

Here, Person class is taking a parcel and getting data in same an order during writing.

Now during intent getExtra and putExtra code is given bellow:

Put in Extra:

Person person=new Person();
                person.setFirstName("First");
                person.setLastName("Name");
                person.setAge(30);

                Intent intent = new Intent(getApplicationContext(), SECOND_ACTIVITY.class);
                intent.putExtra()
                startActivity(intent); 

Get Extra:

Person person=getIntent().getParcelableExtra("person");

Full Person class is given bellow:

import android.os.Parcel;
import android.os.Parcelable;

public class Person implements Parcelable{
    private String firstName;
    private String lastName;
    private int age;



    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public int getAge() {
        return age;
    }

    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel parcel, int i) {
        parcel.writeString(firstName);
        parcel.writeString(lastName);
        parcel.writeInt(age);
    }

    protected Person(Parcel in) {
        firstName = in.readString();
        lastName = in.readString();
        age = in.readInt();
    }

    public static final Creator<Person> CREATOR = new Creator<Person>() {
        @Override
        public Person createFromParcel(Parcel in) {
            return new Person(in);
        }

        @Override
        public Person[] newArray(int size) {
            return new Person[size];
        }
    };

}

Hope this will help you 
Thanks :)

Create a menu Bar in WPF?

<Container>
    <Menu>
        <MenuItem Header="File">
            <MenuItem Header="New">
               <MenuItem Header="File1"/>
               <MenuItem Header="File2"/>
               <MenuItem Header="File3"/>
            </MenuItem>
            <MenuItem Header="Open"/>
            <MenuItem Header="Save"/>
        </MenuItem>
    </Menu>
</Container>

React Native android build failed. SDK location not found

This answer is for MacOs Catalina user or zsh users as your Mac now uses zsh as the default login shell and interactive shell.

If you follow along with the docs of React Native Setting up the development environment guide. Then do the following.

Firstly check if local.properties file exists or not. If the file does not exist then create and add the following line.

sdk.dir=/Users/<youcomputername>/Library/Android/sdk

After doing the above changes now do the following.

  1. Open ~/.zshrc using a code-editor. In my case I use vim
vim ~/.zshrc
  1. Add the following line for the path.
export ANDROID_HOME="/Users/<yourcomputername>/Library/Android/sdk"
export PATH=$ANDROID_HOME/emulator:$PATH
export PATH=$ANDROID_HOME/tools:$PATH
export PATH=$ANDROID_HOME/tools/bin:$PATH
export PATH=$ANDROID_HOME/platform-tools:$PATH

Make sure to add the above line correctly else it will give you a weird error.

  1. Save the changes and close the editor.

  2. Finally, now compile your changes

source ~/.zshrc

I get this working in my case. I hope this helps you.

How do I build an import library (.lib) AND a DLL in Visual C++?

Does your DLL project have any actual exports? If there are no exports, the linker will not generate an import library .lib file.

In the non-Express version of VS, the import libray name is specfied in the project settings here:

Configuration Properties/Linker/Advanced/Import Library

I assume it's the same in Express (if it even provides the ability to configure the name).

Convert between UIImage and Base64 string

//convert Image to Base64 (Encoding)

let strBase64 = imageData.base64EncodedString(options: .lineLength64Characters)

print(strBase64)

// convert Base64 to Image (Decoding)

let dataDecoded:NSData = NSData(base64EncodedString: strBase64, options: NSDataBase64DecodingOptions(rawValue: 0))!

let decodedimage:UIImage = UIImage(data: dataDecoded)!

print(decodedimage)

yourImageView.image = decodedimage

Can my enums have friendly names?

This is a terrible idea, but it does work.

    public enum myEnum
{
    ThisNameWorks,
    ThisNameDoesntWork149141331,// This Name doesn't work
    NeitherDoesThis1849204824// Neither.does.this;
}

class Program
{
    private static unsafe void ChangeString(string original, string replacement)
    {
        if (original.Length < replacement.Length)
            throw new ArgumentException();

        fixed (char* pDst = original)
        fixed (char* pSrc = replacement)
        {
            // Update the length of the original string
            int* lenPtr = (int*)pDst;
            lenPtr[-1] = replacement.Length;

            // Copy the characters
            for (int i = 0; i < replacement.Length; i++)
                pDst[i] = pSrc[i];
        }
    }

    public static unsafe void Initialize()
    {
        ChangeString(myEnum.ThisNameDoesntWork149141331.ToString(), "This Name doesn't work");
        ChangeString(myEnum.NeitherDoesThis1849204824.ToString(), "Neither.does.this");
    }

    static void Main(string[] args)
    {
        Console.WriteLine(myEnum.ThisNameWorks);
        Console.WriteLine(myEnum.ThisNameDoesntWork149141331);
        Console.WriteLine(myEnum.NeitherDoesThis1849204824);

        Initialize();

        Console.WriteLine(myEnum.ThisNameWorks);
        Console.WriteLine(myEnum.ThisNameDoesntWork149141331);
        Console.WriteLine(myEnum.NeitherDoesThis1849204824);
    }

Requirements

  1. Your enum names must have the same number of characters or more than the string that you want to it to be.

  2. Your enum names shouldn't be repeated anywhere, just in case string interning messes things up

Why this is a bad idea (a few reasons)

  1. Your enum names become ugly beause of the requirements

  2. It relies on you calling the initialization method early enough

  3. Unsafe pointers

  4. If the internal format of string changes, e.g. if the length field is moved, you're screwed

  5. If Enum.ToString() is ever changed so that it returns only a copy, you're screwed

  6. Raymond Chen will complain about your use of undocumented features, and how it's your fault that the CLR team couldn't make an optimization to cut run time by 50%, during his next .NET week.

Full Page <iframe>

For full-screen frame redirects and similar things I have two methods. Both work fine on mobile and desktop.

Note this are complete cross-browser working, valid HTML files. Just change title and src for your needs.

1. this is my favorite:

<!DOCTYPE html>
<meta charset=utf-8>
<title> Title-1 </title>
<meta name=viewport content="width=device-width">
<style>
 html, body, iframe { height:100%; width:100%; margin:0; border:0; display:block }
</style>
<iframe src=src1></iframe>

<!-- More verbose CSS for better understanding:
  html   { height:100% }
  body   { height:100%; margin:0 }
  iframe { height:100%; width:100%; border:0; display:block }
-->

or 2. something like that, slightly shorter:

<!DOCTYPE html>
<meta charset=utf-8>
<title> Title-2 </title>
<meta name=viewport content="width=device-width">
<iframe src=src2 style="position:absolute; top:0; left:0; width:100%; height:100%; border:0">
</iframe>


Note:
The above examples avoid using height:100vh because old browsers don't know it (maybe moot these days) and height:100vh is not always equal to height:100% on mobile browsers (probably not applicable here). Otherwise, vh simplifies things a little bit, so

3. this is an example using vh (not my favorite, less compatible with little advantage)

<!DOCTYPE html>
<meta charset=utf-8>
<title> Title-3 </title>
<meta name=viewport content="width=device-width">
<style>
 body { margin:0 }
 iframe { display:block; width:100%; height:100vh; border:0 }
</style>
<iframe src=src3></iframe>

Match line break with regular expression

You could search for:

<li><a href="#">[^\n]+

And replace with:

$0</a>

Where $0 is the whole match. The exact semantics will depend on the language are you using though.


WARNING: You should avoid parsing HTML with regex. Here's why.

SQL MERGE statement to update data

If you need just update your records in energydata based on data in temp_energydata, assuming that temp_enerydata doesn't contain any new records, then try this:

UPDATE e SET e.kWh = t.kWh
  FROM energydata e INNER JOIN 
       temp_energydata t ON e.webmeterID = t.webmeterID AND 
                            e.DateTime = t.DateTime

Here is working sqlfiddle

But if temp_energydata contains new records and you need to insert it to energydata preferably with one statement then you should definitely go with the answer that Bacon Bits gave.

Get Cell Value from Excel Sheet with Apache Poi

May be by:-

    for(Row row : sheet) {          
        for(Cell cell : row) {              
            System.out.print(cell.getStringCellValue());

        }
    }       

For specific type of cell you can try:

switch (cell.getCellType()) {
case Cell.CELL_TYPE_STRING:
    cellValue = cell.getStringCellValue();
    break;

case Cell.CELL_TYPE_FORMULA:
    cellValue = cell.getCellFormula();
    break;

case Cell.CELL_TYPE_NUMERIC:
    if (DateUtil.isCellDateFormatted(cell)) {
        cellValue = cell.getDateCellValue().toString();
    } else {
        cellValue = Double.toString(cell.getNumericCellValue());
    }
    break;

case Cell.CELL_TYPE_BLANK:
    cellValue = "";
    break;

case Cell.CELL_TYPE_BOOLEAN:
    cellValue = Boolean.toString(cell.getBooleanCellValue());
    break;

}

Copy to Clipboard for all Browsers using javascript

I spent a lot of time looking for a solution to this problem too. Here's what i've found thus far:

If you want your users to be able to click on a button and copy some text, you may have to use Flash.

If you want your users to press Ctrl+C anywhere on the page, but always copy xyz to the clipboard, I wrote an all-JS solution in YUI3 (although it could easily be ported to other frameworks, or raw JS if you're feeling particularly self-loathing).

It involves creating a textbox off the screen which gets highlighted as soon as the user hits Ctrl/CMD. When they hit 'C' shortly after, they copy the hidden text. If they hit 'V', they get redirected to a container (of your choice) before the paste event fires.

This method can work well, because while you listen for the Ctrl/CMD keydown anywhere in the body, the 'A', 'C' or 'V' keydown listeners only attach to the hidden text box (and not the whole body). It also doesn't have to break the users expectations - you only get redirected to the hidden box if you had nothing selected to copy anyway!

Here's what i've got working on my site, but check http://at.cg/js/clipboard.js for updates if there are any:

YUI.add('clipboard', function(Y) {


// Change this to the id of the text area you would like to always paste in to:

pasteBox = Y.one('#pasteDIV');


// Make a hidden textbox somewhere off the page.

Y.one('body').append('<input id="copyBox" type="text" name="result" style="position:fixed; top:-20%;" onkeyup="pasteBox.focus()">');
copyBox = Y.one('#copyBox');


// Key bindings for Ctrl+A, Ctrl+C, Ctrl+V, etc:

// Catch Ctrl/Window/Apple keydown anywhere on the page.
Y.on('key', function(e) {
    copyData();
        //  Uncomment below alert and remove keyCodes after 'down:' to figure out keyCodes for other buttons.
        //  alert(e.keyCode);
        //  }, 'body',  'down:', Y);
}, 'body',  'down:91,224,17', Y);

// Catch V - BUT ONLY WHEN PRESSED IN THE copyBox!!!
Y.on('key', function(e) {
    // Oh no! The user wants to paste, but their about to paste into the hidden #copyBox!!
    // Luckily, pastes happen on keyPress (which is why if you hold down the V you get lots of pastes), and we caught the V on keyDown (before keyPress).
    // Thus, if we're quick, we can redirect the user to the right box and they can unload their paste into the appropriate container. phew.
    pasteBox.select();
}, '#copyBox',  'down:86', Y);

// Catch A - BUT ONLY WHEN PRESSED IN THE copyBox!!!
Y.on('key', function(e) {
    // User wants to select all - but he/she is in the hidden #copyBox! That wont do.. select the pasteBox instead (which is probably where they wanted to be).
    pasteBox.select();
}, '#copyBox',  'down:65', Y);



// What to do when keybindings are fired:

// User has pressed Ctrl/Meta, and is probably about to press A,C or V. If they've got nothing selected, or have selected what you want them to copy, redirect to the hidden copyBox!
function copyData() {
    var txt = '';
    // props to Sabarinathan Arthanari for sharing with the world how to get the selected text on a page, cheers mate!
        if (window.getSelection) { txt = window.getSelection(); }
        else if (document.getSelection) { txt = document.getSelection(); }
        else if (document.selection) { txt = document.selection.createRange().text; }
        else alert('Something went wrong and I have no idea why - please contact me with your browser type (Firefox, Safari, etc) and what you tried to copy and I will fix this immediately!');

    // If the user has nothing selected after pressing Ctrl/Meta, they might want to copy what you want them to copy. 
        if(txt=='') {
                copyBox.select();
        }
    // They also might have manually selected what you wanted them to copy! How unnecessary! Maybe now is the time to tell them how silly they are..?!
        else if (txt == copyBox.get('value')) {
        alert('This site uses advanced copy/paste technology, possibly from the future.\n \nYou do not need to select things manually - just press Ctrl+C! \n \n(Ctrl+V will always paste to the main box too.)');
                copyBox.select();
        } else {
                // They also might have selected something completely different! If so, let them. It's only fair.
        }
}
});

Hope someone else finds this useful :]

text-align: right; not working for <label>

As stated in other answers, label is an inline element. However, you can apply display: inline-block to the label and then center with text-align.

#name_label {
    display: inline-block;
    width: 90%;
    text-align: right;
}

Why display: inline-block and not display: inline? For the same reason that you can't align label, it's inline.

Why display: inline-block and not display: block? You could use display: block, but it will be on another line. display: inline-block combines the properties of inline and block. It's inline, but you can also give it a width, height, and align it.

Deactivate or remove the scrollbar on HTML

Meder Omuraliev suggested to use an event handler and set scrollTo(0,0). This is an example for Wassim-azirar. Bringing it all together, I assume this is the final solution.

We have 3 problems: the scrollbar, scrolling with mouse, and keyboard. This hides the scrollbar:

       html, body{overflow:hidden;}

Unfortunally, you can still scroll with the keyboard: To prevent this, we can:

    function keydownHandler(e) {
var evt = e ? e:event;
  var keyCode = evt.keyCode;

  if (keyCode==38 || keyCode==39 || keyCode==40 || keyCode==37){ //arrow keys
e.preventDefault()
scrollTo(0,0);
}
}

document.onkeydown=keydownHandler;

The scrolling with the mouse just naturally doesn't work after this code, so we have prevented the scrolling.

For example: https://jsfiddle.net/aL7pes70/1/

Order of execution of tests in TestNG

To address specific scenario in question:

@Test
public void Test1() {

}

@Test (dependsOnMethods={"Test1"})
public void Test2() {

}

@Test (dependsOnMethods={"Test2"})
public void Test3() {

}

SQL selecting rows by most recent date with two unique columns

I see most of the developers use inline query without looking out it's impact on huge data.

in simple you can achieve this by:

select a.chargeId, a.chargeType, a.serviceMonth 
from invoice a
left outer join invoice b
on a.chargeId=b.chargeId and a.serviceMonth <b.serviceMonth 
where b.chargeId is null
order by a.serviceMonth desc

The equivalent of wrap_content and match_parent in flutter?

There are actually some options available:

You can use SizedBox.expand to make your widget match parents dimensions, or SizedBox(width: double.infinity) to match only the width or SizedBox(heigth: double.infinity) to match only the heigth.

If you want a wrap_content behavior it depends on the parent widget you are using, for example if you put a button on a column it will behave like wrap_content and to use it like match_parent you can wrap the button with a Expanded widget or a sizedbox.

With a ListView the button gets a match_parent behavior and to get a wrap_content behavior you can wrap it with a Flex widget like Row.

Using an Expanded widget makes a child of a Row, Column, or Flex expand to fill the available space in the main axis (e.g., horizontally for a Row or vertically for a Column). https://docs.flutter.io/flutter/widgets/Expanded-class.html

Using a Flexible widget gives a child of a Row, Column, or Flex the flexibility to expand to fill the available space in the main axis (e.g., horizontally for a Row or vertically for a Column), but, unlike Expanded, Flexible does not require the child to fill the available space. https://docs.flutter.io/flutter/widgets/Flexible-class.html

include external .js file in node.js app

If you just want to test a library from the command line, you could do:

cat somelibrary.js mytestfile.js | node

Does "display:none" prevent an image from loading?

Browsers are getting smarter. Today your browser (depending on the version) might skip the image loading if it can determine it's not useful.

The image has a display:none style but its size may be read by the script. Chrome v68.0 does not load images if the parent is hidden.

You may check it there : http://jsfiddle.net/tnk3j08s/

You could also have checked it by looking at the "network" tab of your browser's developer tools.

Note that if the browser is on a small CPU computer, not having to render the image (and layout the page) will make the whole rendering operation faster but I doubt this is something that really makes sense today.

If you want to prevent the image from loading you may simply not add the IMG element to your document (or set the IMG src attribute to "data:" or "about:blank").

Check image width and height before upload with Javascript

Attach the function to the onchange method of the input type file /onchange="validateimg(this)"/

   function validateimg(ctrl) { 
        var fileUpload = ctrl;
        var regex = new RegExp("([a-zA-Z0-9\s_\\.\-:])+(.jpg|.png|.gif)$");
        if (regex.test(fileUpload.value.toLowerCase())) {
            if (typeof (fileUpload.files) != "undefined") {
                var reader = new FileReader();
                reader.readAsDataURL(fileUpload.files[0]);
                reader.onload = function (e) {
                    var image = new Image();
                    image.src = e.target.result;
                    image.onload = function () {
                        var height = this.height;
                        var width = this.width;
                        if (height < 1100 || width < 750) {
                            alert("At least you can upload a 1100*750 photo size.");
                            return false;
                        }else{
                            alert("Uploaded image has valid Height and Width.");
                            return true;
                        }
                    };
                }
            } else {
                alert("This browser does not support HTML5.");
                return false;
            }
        } else {
            alert("Please select a valid Image file.");
            return false;
        }
    }

WPF Binding to parent DataContext

I dont know about XamGrid but that's what i'll do with a standard wpf DataGrid:

<DataGrid>
    <DataGrid.Columns>
        <DataGridTemplateColumn>
            <DataGridTemplateColumn.CellTemplate>
                <DataTemplate>
                    <TextBlock Text="{Binding DataContext.MyProperty, RelativeSource={RelativeSource AncestorType=MyUserControl}}"/>
                </DataTemplate>
            </DataGridTemplateColumn.CellTemplate>
            <DataGridTemplateColumn.CellEditingTemplate>
                <DataTemplate>
                    <TextBox Text="{Binding DataContext.MyProperty, RelativeSource={RelativeSource AncestorType=MyUserControl}}"/>
                </DataTemplate>
            </DataGridTemplateColumn.CellEditingTemplate>
        </DataGridTemplateColumn>
    </DataGrid.Columns>
</DataGrid>

Since the TextBlock and the TextBox specified in the cell templates will be part of the visual tree, you can walk up and find whatever control you need.

"dd/mm/yyyy" date format in excel through vba

I got it

Cells(1, 1).Value = StartDate
Cells(1, 1).NumberFormat = "dd/mm/yyyy"

Basically, I need to set the cell format, instead of setting the date.

How do I customize Facebook's sharer.php

It appears the following answer no longer works, and Facebook no longer accepts parameters on the Feed Dialog links

You can use the Feed Dialog via URL to emulate the behavior of Sharer.php, but it's a little more complicated. You need a Facebook App setup with the Base URL of the URL you plan to share configured. Then you can do the following:

1) Create a link like:

   http://www.facebook.com/dialog/feed?app_id=[FACEBOOK_APP_ID]' +
        '&link=[FULLY_QUALIFIED_LINK_TO_SHARE_CONTENT]' +
        '&picture=[LINK_TO_IMAGE]' +
        '&name=' + encodeURIComponent('[CONTENT_TITLE]') +
        '&caption=' + encodeURIComponent('[CONTENT_CAPTION]) +
        '&description=' + encodeURIComponent('[CONTENT_DESCRIPTION]') +
        '&redirect_uri=' + FBVars.baseURL + '[URL_TO_REDIRECT_TO_AFTER_SHARE]' +
        '&display=popup';

(obviously replace the [CONTENT] with the appropriate content. Documentation here: https://developers.facebook.com/docs/reference/dialogs/feed)

2) Open that link in a popup window with JavaScript on click of the share link

3) I like to create file (i.e. popupclose.html) to redirect users back to when they finish sharing, this file will contain <script>window.close();</script> to close the popup window

The only downside of using the Feed Dialog (besides setup) is that, if you manage Pages as well, you don't have the ability to choose to share via a Page, only a regular user account can share. And it can give you some really cryptic error messages, most of them are related to the setup of your Facebook app or problems with either the content or URL you are sharing.

How do I make a checkbox required on an ASP.NET form?

Scott's answer will work for classes of checkboxes. If you want individual checkboxes, you have to be a little sneakier. If you're just doing one box, it's better to do it with IDs. This example does it by specific check boxes and doesn't require jQuery. It's also a nice little example of how you can get those pesky control IDs into your Javascript.

The .ascx:

<script type="text/javascript">

    function checkAgreement(source, args)
    {                
        var elem = document.getElementById('<%= chkAgree.ClientID %>');
        if (elem.checked)
        {
            args.IsValid = true;
        }
        else
        {        
            args.IsValid = false;
        }
    }

    function checkAge(source, args)
    {
        var elem = document.getElementById('<%= chkAge.ClientID %>');
        if (elem.checked)
        {
            args.IsValid = true;
        }
        else
        {
            args.IsValid = false;
        }    
    }

</script>

<asp:CheckBox ID="chkAgree" runat="server" />
<asp:Label AssociatedControlID="chkAgree" runat="server">I agree to the</asp:Label>
<asp:HyperLink ID="lnkTerms" runat="server">Terms & Conditions</asp:HyperLink>
<asp:Label AssociatedControlID="chkAgree" runat="server">.</asp:Label>
<br />

<asp:CustomValidator ID="chkAgreeValidator" runat="server" Display="Dynamic"
    ClientValidationFunction="checkAgreement">
    You must agree to the terms and conditions.
    </asp:CustomValidator>

<asp:CheckBox ID="chkAge" runat="server" />
<asp:Label AssociatedControlID="chkAge" runat="server">I certify that I am at least 18 years of age.</asp:Label>        
<asp:CustomValidator ID="chkAgeValidator" runat="server" Display="Dynamic"
    ClientValidationFunction="checkAge">
    You must be 18 years or older to continue.
    </asp:CustomValidator>

And the codebehind:

Protected Sub chkAgreeValidator_ServerValidate(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.ServerValidateEventArgs) _
Handles chkAgreeValidator.ServerValidate
    e.IsValid = chkAgree.Checked
End Sub

Protected Sub chkAgeValidator_ServerValidate(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.ServerValidateEventArgs) _
Handles chkAgeValidator.ServerValidate
    e.IsValid = chkAge.Checked
End Sub

Disable form auto submit on button click

another one:

if(this.checkValidity() == false) {

                $(this).addClass('was-validated');
                e.preventDefault();
                e.stopPropagation();
                e.stopImmediatePropagation();

                return false;
}

phpMyAdmin + CentOS 6.0 - Forbidden

Edit your httpd.conf file as follows:

# nano /etc/httpd/conf/httpd.conf

Add the following lines here:

<Directory "/usr/share/phpmyadmin">
    Order allow,deny
    Allow from all
</Directory>

Issue the following command:

# service httpd restart

If your problem is not solved then disable your SELinux.

Could not load file or assembly 'System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' or one of its dependencies

In my case, I was able to find issue with ScriptManager by setting Debug=true in web.config file

How to pass a list from Python, by Jinja2 to JavaScript

Make some invisible HTML tags like <label>, <p>, <input> etc. and name its id, and the class name is a pattern so that you can retrieve it later.

Let you have two lists maintenance_next[] and maintenance_block_time[] of the same length, and you want to pass these two list's data to javascript using the flask. So you take some invisible label tag and set its tag name is a pattern of list's index and set its class name as value at index.

_x000D_
_x000D_
{% for i in range(maintenance_next|length): %}_x000D_
<label id="maintenance_next_{{i}}" name="{{maintenance_next[i]}}" style="display: none;"></label>_x000D_
<label id="maintenance_block_time_{{i}}" name="{{maintenance_block_time[i]}}" style="display: none;"></label>_x000D_
{% endfor%}
_x000D_
_x000D_
_x000D_

Now you can retrieve the data in javascript using some javascript operation like below -

_x000D_
_x000D_
<script>_x000D_
var total_len = {{ total_len }};_x000D_
 _x000D_
for (var i = 0; i < total_len; i++) {_x000D_
    var tm1 = document.getElementById("maintenance_next_" + i).getAttribute("name");_x000D_
    var tm2 = document.getElementById("maintenance_block_time_" + i).getAttribute("name");_x000D_
    _x000D_
    //Do what you need to do with tm1 and tm2._x000D_
    _x000D_
    console.log(tm1);_x000D_
    console.log(tm2);_x000D_
}_x000D_
</script>
_x000D_
_x000D_
_x000D_

Sharing url link does not show thumbnail image on facebook

My site faces same issue too.

Using Facebook debug tool is no help at all. Fetch new data but not IMAGE CACHE.

I forced facebook to clear IMAGE CACHE by add www. into image url. In your case is remove www. and config web server redirect.

 add/remove www. in image url should solve the problem

Unable to find a @SpringBootConfiguration when doing a JpaTest

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest;
import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureWebMvc;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;



@RunWith(SpringRunner.class)
@DataJpaTest
@SpringBootTest
@AutoConfigureWebMvc
public class RepoTest {

    @Autowired
    private ThingShiftDetailsRepository thingShiftDetailsRepo;

    @Test
    public void findThingShiftDetails() {
            ShiftDetails details = new ShiftDetails();
            details.setThingId(1);

            thingShiftDetailsRepo.save(details);

            ShiftDetails dbDetails = thingShiftDetailsRepo.findByThingId(1);
            System.out.println(dbDetails);
    }
}

Above annotations worked well for me. I am using spring boot with JPA.

Java String split removed empty values

From String.split() API Doc:

Splits this string around matches of the given regular expression. This method works as if by invoking the two-argument split method with the given expression and a limit argument of zero. Trailing empty strings are therefore not included in the resulting array.

Overloaded String.split(regex, int) is more appropriate for your case.

Disable future dates after today in Jquery Ui Datepicker

Change maxDate to current date

maxDate: new Date()

It will set current date as maximum value.

Video 100% width and height

By checking other answers, I used object-fit in CSS:

video {
    object-fit: fill;
}

From MDN (https://developer.mozilla.org/en-US/docs/Web/CSS/object-fit):

The object-fit CSS property specifies how the contents of a replaced element should be fitted to the box established by its used height and width.

Value: fill

The replaced content is sized to fill the element’s content box: the object’s concrete object size is the element’s used width and height.

Hiding elements in responsive layout?

You can enter these module class suffixes for any module to better control where it will show or be hidden.

.visible-phone  
.visible-tablet     
.visible-desktop    
.hidden-phone   
.hidden-tablet  
.hidden-desktop 

http://twitter.github.com/bootstrap/scaffolding.html scroll to bottom

Create Test Class in IntelliJ

With the cursor on the class name declaration I do ALT + Return and my Intellij 14.1.4 offers me a popup with the option to 'Create Test'.

How to convert string to boolean php

Strings always evaluate to boolean true unless they have a value that's considered "empty" by PHP (taken from the documentation for empty):

  1. "" (an empty string);
  2. "0" (0 as a string)

If you need to set a boolean based on the text value of a string, then you'll need to check for the presence or otherwise of that value.

$test_mode_mail = $string === 'true'? true: false;

EDIT: the above code is intended for clarity of understanding. In actual use the following code may be more appropriate:

$test_mode_mail = ($string === 'true');

or maybe use of the filter_var function may cover more boolean values:

filter_var($string, FILTER_VALIDATE_BOOLEAN);

filter_var covers a whole range of values, including the truthy values "true", "1", "yes" and "on". See here for more details.

Playing .mp3 and .wav in Java?

Using MP3 Decoder/player/converter Maven Dependency.

import javazoom.jl.decoder.JavaLayerException;
import javazoom.jl.player.Player;

import java.io.FileInputStream;
import java.io.FileNotFoundException;

public class PlayAudio{

public static void main(String[] args) throws FileNotFoundException {

    try {
        FileInputStream fileInputStream = new FileInputStream("mp.mp3");
        Player player = new Player((fileInputStream));
        player.play();
        System.out.println("Song is playing");
        while(true){
            System.out.println(player.getPosition());
        }
    }catch (Exception e){
        System.out.println(e);
    }

  }

}

No module named setuptools

For python3 is:

sudo apt-get install -y python3-setuptools

Insert a new row into DataTable

@William You can use NewRow method of the datatable to get a blank datarow and with the schema as that of the datatable. You can populate this datarow and then add the row to the datatable using .Rows.Add(DataRow) OR .Rows.InsertAt(DataRow, Position). The following is a stub code which you can modify as per your convenience.

//Creating dummy datatable for testing
DataTable dt = new DataTable();
DataColumn dc = new DataColumn("col1", typeof(String));
dt.Columns.Add(dc);

dc = new DataColumn("col2", typeof(String));
dt.Columns.Add(dc);

dc = new DataColumn("col3", typeof(String));
dt.Columns.Add(dc);

dc = new DataColumn("col4", typeof(String));
dt.Columns.Add(dc);

DataRow dr = dt.NewRow();

dr[0] = "coldata1";
dr[1] = "coldata2";
dr[2] = "coldata3";
dr[3] = "coldata4";

dt.Rows.Add(dr);//this will add the row at the end of the datatable
//OR
int yourPosition = 0;
dt.Rows.InsertAt(dr, yourPosition);

Submit HTML form, perform javascript function (alert then redirect)

Looks like your form is submitting which is the default behaviour, you can stop it with this:

<form action="" method="post" onsubmit="completeAndRedirect();return false;">

insert data into database using servlet and jsp in eclipse

Check that doPost() method of servlet is called from the jsp form and remove conn.commit.

Android: how to handle button click

#1 I use the last one frequently when having buttons on the layout which are not generated (but static obviously).

If you use it in practice and in a business application, pay extra attention here, because when you use source obfuscater like ProGuard, you'll need to mark these methods in your activity as to not be obfuscated.

For archiving some kind of compile-time-security with this approach, have a look at Android Lint (example).


#2 Pros and cons for all methods are almost the same and the lesson should be:

Use what ever is most appropriate or feels most intuitive to you.

If you have to assign the same OnClickListener to multiple button instances, save it in the class-scope (#1). If you need a simple listener for a Button, make an anonymous implementation:

button.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        // Take action.
    }
});

I tend to not implement the OnClickListener in the activity, this gets a little confusing from time to time (especially when you implement multiple other event-handlers and nobody knows what this is all doing).

What good are SQL Server schemas?

They can also provide a kind of naming collision protection for plugin data. For example, the new Change Data Capture feature in SQL Server 2008 puts the tables it uses in a separate cdc schema. This way, they don't have to worry about a naming conflict between a CDC table and a real table used in the database, and for that matter can deliberately shadow the names of the real tables.

How to Navigate from one View Controller to another using Swift

Swift 3

let secondviewController:UIViewController =  self.storyboard?.instantiateViewController(withIdentifier: "StoryboardIdOfsecondviewController") as? SecondViewController

self.navigationController?.pushViewController(secondviewController, animated: true)

How to search text using php if ($text contains "World")

In your case you can just use strpos(), or stripos() for case insensitive search:

if (stripos($text, "world") !== false) {
    echo "True";
}

Save the plots into a PDF

import datetime
import numpy as np
from matplotlib.backends.backend_pdf import PdfPages
import matplotlib.pyplot as plt

# Create the PdfPages object to which we will save the pages:
# The with statement makes sure that the PdfPages object is closed properly at
# the end of the block, even if an Exception occurs.
with PdfPages('multipage_pdf.pdf') as pdf:
    plt.figure(figsize=(3, 3))
    plt.plot(range(7), [3, 1, 4, 1, 5, 9, 2], 'r-o')
    plt.title('Page One')
    pdf.savefig()  # saves the current figure into a pdf page
    plt.close()

    plt.rc('text', usetex=True)
    plt.figure(figsize=(8, 6))
    x = np.arange(0, 5, 0.1)
    plt.plot(x, np.sin(x), 'b-')
    plt.title('Page Two')
    pdf.savefig()
    plt.close()

    plt.rc('text', usetex=False)
    fig = plt.figure(figsize=(4, 5))
    plt.plot(x, x*x, 'ko')
    plt.title('Page Three')
    pdf.savefig(fig)  # or you can pass a Figure object to pdf.savefig
    plt.close()

    # We can also set the file's metadata via the PdfPages object:
    d = pdf.infodict()
    d['Title'] = 'Multipage PDF Example'
    d['Author'] = u'Jouni K. Sepp\xe4nen'
    d['Subject'] = 'How to create a multipage pdf file and set its metadata'
    d['Keywords'] = 'PdfPages multipage keywords author title subject'
    d['CreationDate'] = datetime.datetime(2009, 11, 13)
    d['ModDate'] = datetime.datetime.today()

Convert string with commas to array

I remove the characters '[',']' and do an split with ','

let array = stringObject.replace('[','').replace(']','').split(",").map(String);

UNIX nonblocking I/O: O_NONBLOCK vs. FIONBIO

Prior to standardization there was ioctl(...FIONBIO...) and fcntl(...O_NDELAY...), but these behaved inconsistently between systems, and even within the same system. For example, it was common for FIONBIO to work on sockets and O_NDELAY to work on ttys, with a lot of inconsistency for things like pipes, fifos, and devices. And if you didn't know what kind of file descriptor you had, you'd have to set both to be sure. But in addition, a non-blocking read with no data available was also indicated inconsistently; depending on the OS and the type of file descriptor the read may return 0, or -1 with errno EAGAIN, or -1 with errno EWOULDBLOCK. Even today, setting FIONBIO or O_NDELAY on Solaris causes a read with no data to return 0 on a tty or pipe, or -1 with errno EAGAIN on a socket. However 0 is ambiguous since it is also returned for EOF.

POSIX addressed this with the introduction of O_NONBLOCK, which has standardized behavior across different systems and file descriptor types. Because existing systems usually want to avoid any changes to behavior which might break backward compatibility, POSIX defined a new flag rather than mandating specific behavior for one of the others. Some systems like Linux treat all 3 the same, and also define EAGAIN and EWOULDBLOCK to the same value, but systems wishing to maintain some other legacy behavior for backward compatibility can do so when the older mechanisms are used.

New programs should use fcntl(...O_NONBLOCK...), as standardized by POSIX.

BadValue Invalid or no user locale set. Please ensure LANG and/or LC_* environment variables are set correctly

you have to add the missing local lang helper: for me the missing ones where de_LU de_LU.UTF-8 . Mongo 2.6.4 worked wihtout mongo 2.6.5 throw an error on this

Selenium WebDriver.get(url) does not open the URL

A spent a lot of time on this issue and finally found that selenium 2.44 not working with node version 0.12. Use node version 0.10.38.

php search array key and get value

array_search('20120504', array_keys($your_array));

add new row in gridview after binding C#, ASP.net

try using the cloning technique.

{
    DataGridViewRow row = (DataGridViewRow)yourdatagrid.Rows[0].Clone();
    // then for each of the values use a loop like below.
    int cc = yourdatagrid.Columns.Count;
    for (int i2 = 0; i < cc; i2++)
    {
        row.Cells[i].Value = yourdatagrid.Rows[0].Cells[i].Value;
    }
    yourdatagrid.Rows.Add(row);
    i++;
    }
}

This should work. I'm not sure about how the binding works though. Hopefully it won't prevent this from working.

Set an environment variable in git bash

A normal variable is set by simply assigning it a value; note that no whitespace is allowed around the =:

HOME=c

An environment variable is a regular variable that has been marked for export to the environment.

export HOME
HOME=c

You can combine the assignment with the export statement.

export HOME=c

Cannot resolve the collation conflict between "SQL_Latin1_General_CP1_CI_AS" and "Latin1_General_CI_AS" in the equal to operation

Thanks to marc_s's answer I solved my original problem - inspired to take it a step further and post one approach to transforming a whole table at a time - tsql script to generate the alter column statements:

DECLARE @tableName VARCHAR(MAX)
SET @tableName = 'affiliate'
--EXEC sp_columns @tableName
SELECT  'Alter table ' + @tableName + ' alter column ' + col.name
        + CASE ( col.user_type_id )
            WHEN 231
            THEN ' nvarchar(' + CAST(col.max_length / 2 AS VARCHAR) + ') '
          END + 'collate Latin1_General_CI_AS ' + CASE ( col.is_nullable )
                                                    WHEN 0 THEN ' not null'
                                                    WHEN 1 THEN ' null'
                                                  END
FROM    sys.columns col
WHERE   object_id = OBJECT_ID(@tableName)

gets: ALTER TABLE Affiliate ALTER COLUMN myTable NVARCHAR(4000) COLLATE Latin1_General_CI_AS NOT NULL

I'll admit to being puzzled by the need to col.max_length / 2 -

Create Map in Java

Map<Integer, Point2D> hm = new HashMap<Integer, Point2D>();

What is the difference between .*? and .* regular expressions?

Let's say you have:

<a></a>

<(.*)> would match a></a where as <(.*?)> would match a. The latter stops after the first match of >. It checks for one or 0 matches of .* followed by the next expression.

The first expression <(.*)> doesn't stop when matching the first >. It will continue until the last match of >.

Adding Http Headers to HttpClient

Create a HttpRequestMessage, set the Method to GET, set your headers and then use SendAsync instead of GetAsync.

var client = new HttpClient();
var request = new HttpRequestMessage() {
    RequestUri = new Uri("http://www.someURI.com"),
    Method = HttpMethod.Get,
};
request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("text/plain"));
var task = client.SendAsync(request)
    .ContinueWith((taskwithmsg) =>
    {
        var response = taskwithmsg.Result;

        var jsonTask = response.Content.ReadAsAsync<JsonObject>();
        jsonTask.Wait();
        var jsonObject = jsonTask.Result;
    });
task.Wait();

Gradle: Could not determine java version from '11.0.2'

Getting this error when doing a cordova build android --release

I was able to resolve this, after trying so so many different things, by simply doing :

npm install cordova -g   # to upgrade to version 10.0.0

cordova platform rm android
cordova platform add android    # to upgrade to android version 9.0.0

DataTables: Uncaught TypeError: Cannot read property 'defaults' of undefined

var datatable_jquery_script = document.createElement("script");
datatable_jquery_script.src = "vendor/datatables/jquery.dataTables.min.js";
document.body.appendChild(datatable_jquery_script);
setTimeout(function(){
    var datatable_bootstrap_script = document.createElement("script");
    datatable_bootstrap_script.src = "vendor/datatables/dataTables.bootstrap4.min.js";
    document.body.appendChild(datatable_bootstrap_script);
},100);

I used setTimeOut to make sure datatables.min.js loads first. I inspected the waterfall loading of each, bootstrap4.min.js always loads first.

How to do case insensitive string comparison?

Convert both to lower (only once for performance reasons) and compare them with ternary operator in a single line:

function strcasecmp(s1,s2){
    s1=(s1+'').toLowerCase();
    s2=(s2+'').toLowerCase();
    return s1>s2?1:(s1<s2?-1:0);
}

How to keep environment variables when using sudo

First you need to export HTTP_PROXY. Second, you need to read man sudo carefully, and pay attention to the -E flag. This works:

$ export HTTP_PROXY=foof
$ sudo -E bash -c 'echo $HTTP_PROXY'

Here is the quote from the man page:

-E, --preserve-env
             Indicates to the security policy that the user wishes to preserve their
             existing environment variables.  The security policy may return an error
             if the user does not have permission to preserve the environment.

How to determine the version of android SDK installed in computer?

Create a Batch file (.bat) in Windows with the following command in it:

%ANDROID_HOME%\tools\bin\sdkmanager.bat --list && pause

NOTE: Using && pause is necessary to be able to review the information, once it is listed. If not used, the batch file will simply run, show the information in just mere few seconds and exit right away.

Passing multiple parameters to pool.map() function in Python

You can use functools.partial for this (as you suspected):

from functools import partial

def target(lock, iterable_item):
    for item in iterable_item:
        # Do cool stuff
        if (... some condition here ...):
            lock.acquire()
            # Write to stdout or logfile, etc.
            lock.release()

def main():
    iterable = [1, 2, 3, 4, 5]
    pool = multiprocessing.Pool()
    l = multiprocessing.Lock()
    func = partial(target, l)
    pool.map(func, iterable)
    pool.close()
    pool.join()

Example:

def f(a, b, c):
    print("{} {} {}".format(a, b, c))

def main():
    iterable = [1, 2, 3, 4, 5]
    pool = multiprocessing.Pool()
    a = "hi"
    b = "there"
    func = partial(f, a, b)
    pool.map(func, iterable)
    pool.close()
    pool.join()

if __name__ == "__main__":
    main()

Output:

hi there 1
hi there 2
hi there 3
hi there 4
hi there 5

7-Zip command to create and extract a password-protected ZIP file on Windows?

From http://www.dotnetperls.com:

7z a secure.7z * -pSECRET

Where:

7z        : name and path of 7-Zip executable
a         : add to archive
secure.7z : name of destination archive
*         : add all files from current directory to destination archive
-pSECRET  : specify the password "SECRET"

To open :

7z x secure.7z

Then provide the SECRET password

Note: If the password contains spaces or special characters, then enclose it with single quotes

7z a secure.7z * -p"pa$$word @|"

PostgreSQL unnest() with element number

unnest2() as exercise

Older versions before pg v8.4 need a user-defined unnest(). We can adapt this old function to return elements with an index:

CREATE FUNCTION unnest2(anyarray)
  RETURNS setof record  AS
$BODY$
  SELECT $1[i], i
  FROM   generate_series(array_lower($1,1),
                         array_upper($1,1)) i;
$BODY$ LANGUAGE sql IMMUTABLE;

Getting the location from an IP address

Look at the API from hostip.info - it provides lots of information.
Example in PHP:

$data = file_get_contents("http://api.hostip.info/country.php?ip=12.215.42.19");
//$data contains: "US"

$data = file_get_contents("http://api.hostip.info/?ip=12.215.42.19");
//$data contains: XML with country, lat, long, city, etc...

If you trust hostip.info, it seems to be a very useful API.

Show image using file_get_contents

You can do that, or you can use the readfile function, which outputs it for you:

header('Content-Type: image/x-png'); //or whatever
readfile('thefile.png');
die();

Edit: Derp, fixed obvious glaring typo.

typesafe select onChange event using reactjs and typescript

JSX:

<select value={ this.state.foo } onChange={this.handleFooChange}>
    <option value="A">A</option>
    <option value="B">B</option>
</select>

TypeScript:

private handleFooChange = (event: React.FormEvent<HTMLSelectElement>) => {
    const element = event.target as HTMLSelectElement;
    this.setState({ foo: element.value });
}

How do I reverse a C++ vector?

#include<algorithm>
#include<vector>
#include<iostream>
using namespace std;
int main()
{
    vector<int>v1;
    for(int i=0; i<5; i++)
        v1.push_back(i*2);
    for(int i=0; i<v1.size(); i++)
        cout<<v1[i];    //02468
    reverse(v1.begin(),v1.end());
    
    for(int i=0; i<v1.size(); i++)
        cout<<v1[i];   //86420
}

Difference of two date time in sql server

So this isn't my answer but I just found this while searching around online for a question like this as well. This guy set up a procedure to calculate hours, minutes and seconds. The link and the code:

--Creating Function
If OBJECT_ID('UFN_HourMinuteSecond') Is Not Null
Drop Function dbo.UFN_HourMinuteSecond
Go
Exec(
'Create Function dbo.UFN_HourMinuteSecond
(
@StartDateTime DateTime,
@EndDateTime DateTime
) Returns Varchar(10) 
As
Begin

Declare @Seconds Int,
@Minute Int,
@Hour Int,
@Elapsed Varchar(10)

Select @Seconds = ABS(DateDiff(SECOND ,@StartDateTime,@EndDateTime))

If @Seconds >= 60 
Begin
select @Minute = @Seconds/60
select @Seconds = @Seconds%60

If @Minute >= 60
begin
select @hour = @Minute/60
select @Minute = @Minute%60
end

Else
Goto Final 
End

Final:
Select @Hour = Isnull(@Hour,0), @Minute = IsNull(@Minute,0), @Seconds =               IsNull(@Seconds,0)
select @Elapsed = Cast(@Hour as Varchar) + '':'' + Cast(@Minute as Varchar) + '':'' +     Cast(@Seconds as Varchar)

Return (@Elapsed)
End'
)

How do I remove background-image in css?

When background-image: none !important; have no effect. You can use:

background-size: 0 !important;

HTML5 Pre-resize images before uploading

The accepted answer works great, but the resize logic ignores the case in which the image is larger than the maximum in only one of the axes (for example, height > maxHeight but width <= maxWidth).

I think the following code takes care of all cases in a more straight-forward and functional way (ignore the typescript type annotations if using plain javascript):

private scaleDownSize(width: number, height: number, maxWidth: number, maxHeight: number): {width: number, height: number} {
    if (width <= maxWidth && height <= maxHeight)
      return { width, height };
    else if (width / maxWidth > height / maxHeight)
      return { width: maxWidth, height: height * maxWidth / width};
    else
      return { width: width * maxHeight / height, height: maxHeight };
  }

Getting the filenames of all files in a folder

You could do it like that:

File folder = new File("your/path");
File[] listOfFiles = folder.listFiles();

for (int i = 0; i < listOfFiles.length; i++) {
  if (listOfFiles[i].isFile()) {
    System.out.println("File " + listOfFiles[i].getName());
  } else if (listOfFiles[i].isDirectory()) {
    System.out.println("Directory " + listOfFiles[i].getName());
  }
}

Do you want to only get JPEG files or all files?

TimeSpan to DateTime conversion

First, convert the timespan to a string, then to DateTime, then back to a string:

Convert.ToDateTime(timespan.SelectedTime.ToString()).ToShortTimeString();

"Call to undefined function mysql_connect()" after upgrade to php-7

From the PHP Manual:

Warning This extension was deprecated in PHP 5.5.0, and it was removed in PHP 7.0.0. Instead, the MySQLi or PDO_MySQL extension should be used. See also MySQL: choosing an API guide. Alternatives to this function include:

mysqli_connect()

PDO::__construct()

use MySQLi or PDO

<?php
$con = mysqli_connect('localhost', 'username', 'password', 'database');

Adding sheets to end of workbook in Excel (normal method not working?)

Be sure to fully qualify your sheets with which workbook they are referencing!

 mainWB.Sheets.Add(After:=mainWB.Sheets(mainWB.Sheets.Count)).Name = new_sheet_name

How to take the first N items from a generator or list?

With itertools you will obtain another generator object so in most of the cases you will need another step the take the first N elements (N). There are at least two simpler solutions (a little bit less efficient in terms of performance but very handy) to get the elements ready to use from a generator:

Using list comprehension:

first_N_element=[generator.next() for i in range(N)]

Otherwise:

first_N_element=list(generator)[:N]

Where N is the number of elements you want to take (e.g. N=5 for the first five elements).

Convert to absolute value in Objective-C

You can use this function to get the absolute value:

+(NSNumber *)absoluteValue:(NSNumber *)input {
  return [NSNumber numberWithDouble:fabs([input doubleValue])];
}

HttpServletRequest - Get query string parameters, no form data

Contrary to what cularis said there can be both in the parameter map.

The best way I see is to proxy the parameterMap and for each parameter retrieval check if queryString contains "&?<parameterName>=".

Note that parameterName needs to be URL encoded before this check can be made, as Qerub pointed out.

That saves you the parsing and still gives you only URL parameters.

Why can't I push to this bare repository?

This related question's answer provided the solution for me... it was just a dumb mistake:

Remember to commit first!

https://stackoverflow.com/a/7572252

If you have not yet committed to your local repo, there is nothing to push, but the Git error message you get back doesn't help you too much.

.htaccess deny from all

This syntax has changed with the newer Apache HTTPd server, please see upgrade to apache 2.4 doc for full details.

2.2 configuration syntax was

Order deny,allow
Deny from all

2.4 configuration now is

Require all denied

Thus, this 2.2 syntax

order deny,allow
deny from all
allow from 127.0.0.1

Would ne now written

Require local

SQL - Query to get server's IP address

A simpler way to get the machine name without the \InstanceName is:

SELECT SERVERPROPERTY('MachineName')

Generate SQL Create Scripts for existing tables with Query

Since we're offering alternatives to what you asked..

If you're in .Net, you should look at the Database Publishing Wizard in Visual Studio. Easy way to script your tables/data to a text file.

http://www.codeplex.com/sqlhost/Wiki/View.aspx?title=Database%20Publishing%20Wizard

Error With Port 8080 already in use

I faced a similar problem , here's the solution.

Step 1 : Double click on the server listed in Eclipse. Here It will display Server Configuration.

Step 2 : Just change the port Number like from 8080 to 8085.

Step 3 : Save the changes.

Step 4 : re-start your server.

The server will start .Hope it'll help you.

ValueError: unsupported pickle protocol: 3, python2 pickle can not load the file dumped by python 3 pickle?

You should write the pickled data with a lower protocol number in Python 3. Python 3 introduced a new protocol with the number 3 (and uses it as default), so switch back to a value of 2 which can be read by Python 2.

Check the protocolparameter in pickle.dump. Your resulting code will look like this.

pickle.dump(your_object, your_file, protocol=2)

There is no protocolparameter in pickle.load because pickle can determine the protocol from the file.

How Best to Compare Two Collections in Java and Act on Them?

For a set that small is generally not worth it to convert from an Array to a HashMap/set. In fact, you're probably best off keeping them in an array and then sorting them by key and iterating over both lists simultaneously to do the comparison.

List directory tree structure in python?

On top of dhobbs answer above (https://stackoverflow.com/a/9728478/624597), here is an extra functionality of storing results to a file (I personally use it to copy and paste to FreeMind to have a nice overview of the structure, therefore I used tabs instead of spaces for indentation):

import os

def list_files(startpath):

    with open("folder_structure.txt", "w") as f_output:
        for root, dirs, files in os.walk(startpath):
            level = root.replace(startpath, '').count(os.sep)
            indent = '\t' * 1 * (level)
            output_string = '{}{}/'.format(indent, os.path.basename(root))
            print(output_string)
            f_output.write(output_string + '\n')
            subindent = '\t' * 1 * (level + 1)
            for f in files:
                output_string = '{}{}'.format(subindent, f)
                print(output_string)
                f_output.write(output_string + '\n')

list_files(".")

Create list of object from another using Java 8 Streams

An addition to the solution by @Rafael Teles. The syntactic sugar Collectors.mapping does the same in one step:

//...
List<Employee> employees = persons.stream()
  .filter(p -> p.getLastName().equals("l1"))
  .collect(
    Collectors.mapping(
      p -> new Employee(p.getName(), p.getLastName(), 1000),
      Collectors.toList()));

Detailed example can be found here

Controlling Spacing Between Table Cells

Use border-collapse and border-spacing to get spaces between the table cells. I would not recommend using floating cells as suggested by QQping.

JSFiddle

Error in Python IOError: [Errno 2] No such file or directory: 'data.csv'

You need to either provide the absolute path to data.csv, or run your script in the same directory as data.csv.

Convert JSON String to JSON Object c#

JObject defines method Parse for this:

JObject json = JObject.Parse(str);

You might want to refer to Json.NET documentation.

How to write some data to excel file(.xlsx)

You can use ClosedXML for this.

Store your table in a DataTable and you can export the table to excel by this simple snippet:

XLWorkbook workbook = new XLWorkbook();
DataTable table = GetYourTable();
workbook.Worksheets.Add(table );

You can read the documentation of ClosedXML to learn more. Hope this helps!

Twitter bootstrap float div right

This does the trick, without the need to add an inline style

<div class="row-fluid">
    <div class="span6">
        <p>text left</p>
    </div>
    <div class="span6">
        <div class="pull-right">
            <p>text right</p>
        </div>
    </div>
</div>

The answer is in nesting another <div> with the "pull-right" class. Combining the two classes won't work.

Replace preg_replace() e modifier with preg_replace_callback

In a regular expression, you can "capture" parts of the matched string with (brackets); in this case, you are capturing the (^|_) and ([a-z]) parts of the match. These are numbered starting at 1, so you have back-references 1 and 2. Match 0 is the whole matched string.

The /e modifier takes a replacement string, and substitutes backslash followed by a number (e.g. \1) with the appropriate back-reference - but because you're inside a string, you need to escape the backslash, so you get '\\1'. It then (effectively) runs eval to run the resulting string as though it was PHP code (which is why it's being deprecated, because it's easy to use eval in an insecure way).

The preg_replace_callback function instead takes a callback function and passes it an array containing the matched back-references. So where you would have written '\\1', you instead access element 1 of that parameter - e.g. if you have an anonymous function of the form function($matches) { ... }, the first back-reference is $matches[1] inside that function.

So a /e argument of

'do_stuff(\\1) . "and" . do_stuff(\\2)'

could become a callback of

function($m) { return do_stuff($m[1]) . "and" . do_stuff($m[2]); }

Or in your case

'strtoupper("\\2")'

could become

function($m) { return strtoupper($m[2]); }

Note that $m and $matches are not magic names, they're just the parameter name I gave when declaring my callback functions. Also, you don't have to pass an anonymous function, it could be a function name as a string, or something of the form array($object, $method), as with any callback in PHP, e.g.

function stuffy_callback($things) {
    return do_stuff($things[1]) . "and" . do_stuff($things[2]);
}
$foo = preg_replace_callback('/([a-z]+) and ([a-z]+)/', 'stuffy_callback', 'fish and chips');

As with any function, you can't access variables outside your callback (from the surrounding scope) by default. When using an anonymous function, you can use the use keyword to import the variables you need to access, as discussed in the PHP manual. e.g. if the old argument was

'do_stuff(\\1, $foo)'

then the new callback might look like

function($m) use ($foo) { return do_stuff($m[1], $foo); }

Gotchas

  • Use of preg_replace_callback is instead of the /e modifier on the regex, so you need to remove that flag from your "pattern" argument. So a pattern like /blah(.*)blah/mei would become /blah(.*)blah/mi.
  • The /e modifier used a variant of addslashes() internally on the arguments, so some replacements used stripslashes() to remove it; in most cases, you probably want to remove the call to stripslashes from your new callback.

gcc warning" 'will be initialized after'

You can disable it with -Wno-reorder.

Disable Logback in SpringBoot

The reason is, spring boot comes with logback as its default log configuration whereas camel uses log4j. Thats the reason of conflict. You have two options, either remove logback from spring boot as mentioned in above answers or remove log4j from camel.

<dependency>
            <groupId>org.apache.camel</groupId>
            <artifactId>camel-spring-boot-starter</artifactId>
            <version>${camel.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

numpy get index where value is true

A simple and clean way: use np.argwhere to group the indices by element, rather than dimension as in np.nonzero(a) (i.e., np.argwhere returns a row for each non-zero element).

>>> a = np.arange(10)
>>> a
array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])
>>> np.argwhere(a>4)
array([[5],
       [6],
       [7],
       [8],
       [9]])

np.argwhere(a) is the same as np.transpose(np.nonzero(a)).

Note: You cannot use a(np.argwhere(a>4)) to get the corresponding values in a. The recommended way is to use a[(a>4).astype(bool)] or a[(a>4) != 0] rather than a[np.nonzero(a>4)] as they handle 0-d arrays correctly. See the documentation for more details. As can be seen in the following example, a[(a>4).astype(bool)] and a[(a>4) != 0] can be simplified to a[a>4].

Another example:

>>> a = np.array([5,-15,-8,-5,10])
>>> a
array([  5, -15,  -8,  -5,  10])
>>> a > 4
array([ True, False, False, False,  True])
>>> a[a > 4]
array([ 5, 10])
>>> a = np.add.outer(a,a)
>>> a
array([[ 10, -10,  -3,   0,  15],
       [-10, -30, -23, -20,  -5],
       [ -3, -23, -16, -13,   2],
       [  0, -20, -13, -10,   5],
       [ 15,  -5,   2,   5,  20]])
>>> a = np.argwhere(a>4)
>>> a
array([[0, 0],
       [0, 4],
       [3, 4],
       [4, 0],
       [4, 3],
       [4, 4]])
>>> [print(i,j) for i,j in a]
0 0
0 4
3 4
4 0
4 3
4 4

Specify a Root Path of your HTML directory for script links?

Just start it with a slash? This means root. As long as you're testing on a web server (e.g. localhost) and not a file system (e.g. C:) then that should be all you need to do.

How to loop through elements of forms with JavaScript?

You can iterate named fields somehow like this:

let jsonObject = {};
for(let field of form.elements) {
  if (field.name) {
      jsonObject[field.name] = field.value;
  }
}

Or, if you need only submiting fields:

function formDataToJSON(form) {
  let jsonObject = {};
  let formData = new FormData(form);
  for(let field of formData) {
      jsonObject[field[0]] = field[1];
  }
  return JSON.stringify(jsonObject);
}

jQuery.each - Getting li elements inside an ul

First I think you need to fix your lists, as the first node of a <ul> must be a <li> (stackoverflow ref). Once that is setup you can do this:

// note this array has outer scope
var phrases = [];

$('.phrase').each(function(){
        // this is inner scope, in reference to the .phrase element
        var phrase = '';
        $(this).find('li').each(function(){
            // cache jquery var
            var current = $(this);
            // check if our current li has children (sub elements)
            // if it does, skip it
            // ps, you can work with this by seeing if the first child
            // is a UL with blank inside and odd your custom BLANK text
            if(current.children().size() > 0) {return true;}
            // add current text to our current phrase
            phrase += current.text();
        });
        // now that our current phrase is completely build we add it to our outer array
        phrases.push(phrase);
    });
    // note the comma in the alert shows separate phrases
    alert(phrases);

Working jsfiddle.

One thing is if you get the .text() of an upper level li you will get all sub level text with it.

Keeping an array will allow for many multiple phrases to be extracted.


EDIT:

This should work better with an empty UL with no LI:

// outer scope
var phrases = [];

$('.phrase').each(function(){
    // inner scope
    var phrase = '';
    $(this).find('li').each(function(){
        // cache jquery object
        var current = $(this);
        // check for sub levels
        if(current.children().size() > 0) {
            // check is sublevel is just empty UL
            var emptyULtest = current.children().eq(0); 
            if(emptyULtest.is('ul') && $.trim(emptyULtest.text())==""){
                phrase += ' -BLANK- '; //custom blank text
                return true;   
            } else {
             // else it is an actual sublevel with li's
             return true;   
            }
        }
        // if it gets to here it is actual li
        phrase += current.text();
    });
    phrases.push(phrase);
});
// note the comma to separate multiple phrases
alert(phrases);

JavaScript: how to change form action attribute value based on selection?

$("#selectsearch").change(function() {
  var action = $(this).val() == "people" ? "user" : "content";
  $("#search-form").attr("action", "/search/" + action);
});

pandas GroupBy columns with NaN (missing) values

Ancient topic, if someone still stumbles over this--another workaround is to convert via .astype(str) to string before grouping. That will conserve the NaN's.

df = pd.DataFrame({'a': ['1', '2', '3'], 'b': ['4', np.NaN, '6']})
df['b'] = df['b'].astype(str)
df.groupby(['b']).sum()
    a
b   
4   1
6   3
nan 2

How to fix System.NullReferenceException: Object reference not set to an instance of an object

I had the same problem but it only occurred on the published website on Godaddy. It was no problem in my local host.

The error came from an aspx.cs (code behind file) where I tried to assign a value to a label. It appeared that from within the code behind, that the label Text appears to be null. So all I did with change all my Label Text properties in the ASPX file from Text="" to Text=" ".

The problem disappeared. I don’t know why the error happens from the hosted version but not on my localhost and don’t have time to figure out why. But it works fine now.

Regex to check whether a string contains only numbers

As you said, you want hash to contain only numbers.

var reg = new RegExp('^[0-9]+$');

or

var reg = new RegExp('^\\d+$');

\d and [0-9] both mean the same thing. The + used means that search for one or more occurring of [0-9].

What exactly does Double mean in java?

Double is a wrapper class,

The Double class wraps a value of the primitive type double in an object. An object of type Double contains a single field whose type is double.

In addition, this class provides several methods for converting a double to a String and a String to a double, as well as other constants and methods useful when dealing with a double.

The double data type,

The double data type is a double-precision 64-bit IEEE 754 floating point. Its range of values is 4.94065645841246544e-324d to 1.79769313486231570e+308d (positive or negative). For decimal values, this data type is generally the default choice. As mentioned above, this data type should never be used for precise values, such as currency.

Check each datatype with their ranges : Java's Primitive Data Types.


Important Note : If you'r thinking to use double for precise values, you need to re-think before using it. Java Traps: double

ASP.NET Core Identity - get current user

Assuming your code is inside an MVC controller:

public class MyController : Microsoft.AspNetCore.Mvc.Controller

From the Controller base class, you can get the IClaimsPrincipal from the User property

System.Security.Claims.ClaimsPrincipal currentUser = this.User;

You can check the claims directly (without a round trip to the database):

bool IsAdmin = currentUser.IsInRole("Admin");
var id = _userManager.GetUserId(User); // Get user id:

Other fields can be fetched from the database's User entity:

  1. Get the user manager using dependency injection

    private UserManager<ApplicationUser> _userManager;
    
    //class constructor
    public MyController(UserManager<ApplicationUser> userManager)
    {
        _userManager = userManager;
    }
    
  2. And use it:

    var user = await _userManager.GetUserAsync(User);
    var email = user.Email;
    

How to increase dbms_output buffer?

Here you go:

DECLARE
BEGIN
  dbms_output.enable(NULL); -- Disables the limit of DBMS
  -- Your print here !
END;