Programs & Examples On #Texnic center

TeXnicCenter is a feature rich and easy-to-use integrated environment for creating LaTeX documents on the Windows platform.

replace all occurrences in a string

Brighams answer uses literal regexp.

Solution with a Regex object.

var regex = new RegExp('\n', 'g');
text = text.replace(regex, '<br />');

TRY IT HERE : JSFiddle Working Example

Initialize empty vector in structure - c++

Like this:

#include <string>
#include <vector>

struct user
    std::string username;
    std::vector<unsigned char> userpassword;

int main()
    user r;   // r.username is "" and r.userpassword is empty
    // ...

Python Linked List

I've put a Python 2.x and 3.x singly-linked list class at

It's tested with CPython 2.7, CPython 3.4, Pypy 2.3.1, Pypy3 2.3.1, and Jython 2.7b2, and comes with a nice automated test suite.

It also includes LIFO and FIFO classes.

They aren't immutable though.

how to set default culture info for entire c# application

If you use a Language Resource file to set the labels in your application you need to set the its value:

CultureInfo customCulture = new CultureInfo("en-US");
Languages.Culture = customCulture;

Delete directories recursively in Java

If you have Spring, you can use FileSystemUtils.deleteRecursively:

import org.springframework.util.FileSystemUtils;

boolean success = FileSystemUtils.deleteRecursively(new File("directory"));

Create Windows service from executable

I created the cross-platform Service Manager software a few years back so that I could start PHP and other scripting languages as system services on Windows, Mac, and Linux OSes:

Service Manager is a set of precompiled binaries that install and manage a system service on the target OS using nearly identical command-line options (source code also available). Each platform does have subtle differences but the core features are mostly normalized.

If the child process dies, Service Manager automatically restarts it.

Processes that are started with Service Manager should periodically watch for two notification files to handle restart and reload requests but they don't necessarily have to do that. Service Manager will force restart the child process if it doesn't respond in a timely fashion to controlled restart/reload requests.

How to randomly select an item from a list?

The following code demonstrates if you need to produce the same items. You can also specify how many samples you want to extract.
The sample method returns a new list containing elements from the population while leaving the original population unchanged. The resulting list is in selection order so that all sub-slices will also be valid random samples.

import random as random
random.seed(0)  # don't use seed function, if you want different results in each run
print(random.sample(foo,3))  # 3 is the number of sample you want to retrieve

Output:['d', 'e', 'a']

Get the current date and time

DateTimePicker1.value = Format(Date.Now)

How to insert text at beginning of a multi-line selection in vi/Vim

For commenting blocks of code, I like the NERD Commenter plugin.

Select some text:

Shift-V the lines of text you want to comment....





Or just toggle the comment state of a line or block:


Set default time in bootstrap-datetimepicker

This is my solution for your problem :

language: 'en',
format: 'yyyy-MM-dd hh:mm'
}).on('dp.change', function (e) {
        var specifiedDate = new Date(;
        if (specifiedDate.getMinutes() == 0)

This also work for setting a default hour or both. Note that this code sample works with the useCurrent: false parameter too.

When the user pick a date, we check if the minute is 0 (hard-coded default value). In this case, we set a 1. Then, the user cannot select 0.

Uninitialized Constant MessagesController

Your model is @Messages, change it to @message.

To change it like you should use migration:

def change   rename_table :old_table_name, :new_table_name end 

Of course do not create that file by hand but use rails generator:

rails g migration ChangeMessagesToMessage 

That will generate new file with proper timestamp in name in 'db dir. Then run:

rake db:migrate 

And your app should be fine since then.

Editable 'Select' element

Another sort of workaround might be...

Use the HTML:

<input type="text" id="myselect"/>
<datalist id="myselect">
<option>option 1</option>
<option>option 2</option>
<option>option 3</option>
<option>option 4</option>

In Firefox at least a focus followed by a click drops down the list of known valid values as the <datalist> elements IFF the field happens to be empty. Otherwise, one must clear the field to see valid choices as one types in data. A new value is accepted as typed. One must handle new values in JS or other to persist them.

This is not perfect, but it suffices for my minimalist needs, so I thought I would share.

How to open up a form from another form in VB.NET?

You may like to first create a dialogue by right clicking the project in solution explorer and in the code file type

that's all !!!

What is The difference between ListBox and ListView

Listview derives from listbox control. One most important difference is listview uses the extended selection mode by default . listview also adds a property called view which enables you to customize the view in a richer way than a custom itemspanel. One real life example of listview with gridview is file explorer's details view. Listview with grid view is a less powerful data grid. After the introduction of datagrid control listview lost its importance.

How do I open a new window using jQuery?

Those are by no means the same. The first will simply send you to whatever URL you have assigned to window.location.href (in the same window you're currently in). The second makes a GET AJAX request.

Try this page:

It gives a great example on how to open a new window*.

If you wish to use raw javascript then this is what you're looking for:,name,specs,replace)

As seen in

The entity cannot be constructed in a LINQ to Entities query

In many cases, the transformation is not needed. Think for the reason you want the strongly type List, and evaluate if you just want the data, for example, in a web service or for displaying it. It does not matter the type. You just need to know how to read it and check that is identical to the properties defined in the anonymous type that you defined. That is the optimun scenario, cause something you don't need all the fields of an entity, and that's the reason anonymous type exists.

A simple way is doing this:

IEnumerable<object> list = dataContext.Table.Select(e => new { MyRequiredField = e.MyRequiredField}).AsEnumerable();

Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.2:java (default-cli)

To solve this problem in IntelliJ...
1) Put your .fxml files into resources directory
2) In the Start method define the path to .fxml file in the following way:
Parent root = FXMLLoader.load(getClass().getResource("/sample.fxml"));
The / seemed to solve this problem for me :)

Angular 2 beta.17: Property 'map' does not exist on type 'Observable<Response>'


Add the below command in your *.service.ts file"

import { map } from "rxjs/operators";

.pipe(map(res => res.json()));

I am using windows 10;

angular6 with typescript V

What is a LAMP stack?

Linux, Apache, MySQL and PHP. free and open-source software. For example, an equivalent installation on the Microsoft Windows family of operating systems is known as WAMP. and for mac as MAMP. and XAMPP for both of them

Setting format and value in input type="date"

It's ugly, but it works. :/

var today = new Date().toLocaleString('en-GB').split(' ')[0].split('/').reverse().join('-');

What is the difference between function and procedure in PL/SQL?

In dead simple way it makes this meaning.

Functions :

These subprograms return a single value; mainly used to compute and return a value.

Procedure :

These subprograms do not return a value directly; mainly used to perform an action.

Example Program:



dbms_output.put_line('Hello World!');


Executing a Standalone Procedure :

A standalone procedure can be called in two ways:

• Using the EXECUTE keyword • Calling the name of procedure from a PL/SQL block

The procedure can also be called from another PL/SQL block:



RETURN number IS
total number(3) := 0;
SELECT count(*) into total 
FROM employees;
RETURN total; 

Following program calls the function totalCustomers from an another block

c number(3);
c := totalEmployees();
dbms_output.put_line('Total no. of Employees: ' || c);

Check if value exists in column in VBA

Try adding WorksheetFunction:

If Not IsError(Application.WorksheetFunction.Match(ValueToSearchFor, RangeToSearchIn, 0)) Then
' String is in range

Create instance of generic type whose constructor requires a parameter?

I created this method:

public static V ConvertParentObjToChildObj<T,V> (T obj) where V : new()
    Type typeT = typeof(T);
    PropertyInfo[] propertiesT = typeT.GetProperties();
    V newV = new V();
    foreach (var propT in propertiesT)
        var nomePropT = propT.Name;
        var valuePropT = propT.GetValue(obj, null);

        Type typeV = typeof(V);
        PropertyInfo[] propertiesV = typeV.GetProperties();
        foreach (var propV in propertiesV)
            var nomePropV = propV.Name;
            if(nomePropT == nomePropV)
                propV.SetValue(newV, valuePropT);
    return newV;

I use that in this way:

public class A 
    public int PROP1 {get; set;}

public class B : A
    public int PROP2 {get; set;}


A instanceA = new A();
instanceA.PROP1 = 1;

B instanceB = new B();
instanceB = ConvertParentObjToChildObj<A,B>(instanceA);

Installing TensorFlow on Windows (Python 3.6.x)

For Pip installation on Windows and 64-bit Python 3.5:

CPU only version:

C:\> pip install --upgrade

For the GPU version:

C:\> pip install --upgrade

References: Tensorflow installation issue on windows "tensorflow_gpu-0.12.0rc0-cp35-cp35m-win_amd64.whl is not a supported wheel on th is platform.".

Also see tensorflow not found in pip.

Uncaught TypeError: Cannot set property 'value' of null

The problem may where the code is being executed. If you are in the head of a document executing JavaScript, even when you have an element with id="u" in your web page, the code gets executed before the DOM is finished loading, and so none of the HTML really exists yet... You can fix this by moving your code to the end of the page just above the closing html tag. This is one good reason to use jQuery.

How to change the name of a Django app?

Fun problem! I'm going to have to rename a lot of apps soon, so I did a dry run.

This method allows progress to be made in atomic steps, to minimise disruption for other developers working on the app you're renaming.

See the link at the bottom of this answer for working example code.

  1. Prepare existing code for the move:
    • Create an app config (set name and label to defaults).
    • Add the app config to INSTALLED_APPS.
    • On all models, explicitly set db_table to the current value.
    • Doctor migrations so that db_table was "always" explicitly defined.
    • Ensure no migrations are required (checks previous step).
  2. Change the app label:

    • Set label in app config to new app name.
    • Update migrations and foreign keys to reference new app label.
    • Update templates for generic class-based views (the default path is <app_label>/<model_name>_<suffix>.html)
    • Run raw SQL to fix migrations and content_types app (unfortunately, some raw SQL is unavoidable). You can not run this in a migration.

      UPDATE django_migrations
         SET app = 'catalogue'
       WHERE app = 'shop';
      UPDATE django_content_type
         SET app_label = 'catalogue'
       WHERE app_label = 'shop';
    • Ensure no migrations are required (checks previous step).

  3. Rename the tables:
    • Remove "custom" db_table.
    • Run makemigrations so django can rename the table "to the default".
  4. Move the files:
    • Rename module directory.
    • Fix imports.
    • Update app config's name.
    • Update where INSTALLED_APPS references the app config.
  5. Tidy up:
    • Remove custom app config if it's no longer required.
    • If app config gone, don't forget to also remove it from INSTALLED_APPS.

Example solution: I've created app-rename-example, an example project where you can see how I renamed an app, one commit at a time.

The example uses Python 2.7 and Django 1.8, but I'm confident the same process will work on at least Python 3.6 and Django 2.1.

Including JavaScript class definition from another file in Node.js

You can simply do this:


class User {

module.exports = User


const User = require('./user.js')

// Instantiate User:
let user = new User()

This is called CommonJS module.

Export multiple values

Sometimes it could be useful to export more than one value. For example it could be classes, functions or constants. This is an alternative version of the same functionality:


class User {}

exports.User = User //  Spot the difference


const {User} = require('./user.js') //  Destructure on import

// Instantiate User:
let user = new User()

ES Modules

Since Node.js version 14 it's possible to use ES Modules with CommonJS. Read more about it in the ESM documentation.

?? Don't use globals, it creates potential conflicts with the future code.

How to establish a connection pool in JDBC?


It's modern, it's fast, it's simple. I use it for every new project. I prefer it a lot over C3P0, don't know the other pools too well.

Check if a string is html or not

Here's a sloppy one-liner that I use from time to time:

var isHTML = RegExp.prototype.test.bind(/(<([^>]+)>)/i);

It will basically return true for strings containing a < followed by ANYTHING followed by >.

By ANYTHING, I mean basically anything except an empty string.

It's not great, but it's a one-liner.


isHTML('Testing');               // false
isHTML('<p>Testing</p>');        // true
isHTML('<img src="hello.jpg">'); // true
isHTML('My < weird > string');   // true (caution!!!)
isHTML('<>');                    // false

As you can see it's far from perfect, but might do the job for you in some cases.

How do I write a "tab" in Python?

This is the code:

f = open(filename, 'w')

The \t inside the string is the escape sequence for the horizontal tabulation.

How to go from Blob to ArrayBuffer

You can use FileReader to read the Blob as an ArrayBuffer.

Here's a short example:

var arrayBuffer;
var fileReader = new FileReader();
fileReader.onload = function(event) {
    arrayBuffer =;

Here's a longer example:

// ArrayBuffer -> Blob
var uint8Array  = new Uint8Array([1, 2, 3]);
var arrayBuffer = uint8Array.buffer;
var blob        = new Blob([arrayBuffer]);

// Blob -> ArrayBuffer
var uint8ArrayNew  = null;
var arrayBufferNew = null;
var fileReader     = new FileReader();
fileReader.onload  = function(event) {
    arrayBufferNew =;
    uint8ArrayNew  = new Uint8Array(arrayBufferNew);

    // warn if read values are not the same as the original values
    // arrayEqual from:
    function arrayEqual(a, b) { return !(a<b || b<a); };
    if (arrayBufferNew.byteLength !== arrayBuffer.byteLength) // should be 3
        console.warn("ArrayBuffer byteLength does not match");
    if (arrayEqual(uint8ArrayNew, uint8Array) !== true) // should be [1,2,3]
        console.warn("Uint8Array does not match");
fileReader.result; // also accessible this way once the blob has been read

This was tested out in the console of Chrome 27—69, Firefox 20—60, and Safari 6—11.

Here's also a live demonstration which you can play with:

Update 2018-06-23: Thanks to Klaus Klein for the tip about versus this.result


android get all contacts

Get contacts info , photo contacts , photo uri and convert to Class model

1). Sample for Class model :

    public class ContactModel {
        public String id;
        public String name;
        public String mobileNumber;
        public Bitmap photo;
        public Uri photoURI;

2). get Contacts and convert to Model

     public List<ContactModel> getContacts(Context ctx) {
        List<ContactModel> list = new ArrayList<>();
        ContentResolver contentResolver = ctx.getContentResolver();
        Cursor cursor = contentResolver.query(ContactsContract.Contacts.CONTENT_URI, null, null, null, null);
        if (cursor.getCount() > 0) {
            while (cursor.moveToNext()) {
                String id = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts._ID));
                if (cursor.getInt(cursor.getColumnIndex(ContactsContract.Contacts.HAS_PHONE_NUMBER)) > 0) {
                    Cursor cursorInfo = contentResolver.query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null,
                            ContactsContract.CommonDataKinds.Phone.CONTACT_ID + " = ?", new String[]{id}, null);
                    InputStream inputStream = ContactsContract.Contacts.openContactPhotoInputStream(ctx.getContentResolver(),
                            ContentUris.withAppendedId(ContactsContract.Contacts.CONTENT_URI, new Long(id)));

                    Uri person = ContentUris.withAppendedId(ContactsContract.Contacts.CONTENT_URI, new Long(id));
                    Uri pURI = Uri.withAppendedPath(person, ContactsContract.Contacts.Photo.CONTENT_DIRECTORY);

                    Bitmap photo = null;
                    if (inputStream != null) {
                        photo = BitmapFactory.decodeStream(inputStream);
                    while (cursorInfo.moveToNext()) {
                        ContactModel info = new ContactModel();
               = id;
               = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));
                        info.mobileNumber = cursorInfo.getString(cursorInfo.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
               = photo;
                        info.photoURI= pURI;

        return list;

How can one pull the (private) data of one's own Android app?

Does that mean that one could chmod the directory from world:--x to world:r-x long enough to be able to fetch the files?

Yes, exactly. Weirdly enough, you also need the file to have the x bit set. (at least on Android 2.3)

chmod 755 all the way down worked to copy a file (but you should revert permissions afterwards, if you plan to continue using the device).

Class is not abstract and does not override abstract method

Both classes Rectangle and Ellipse need to override both of the abstract methods.

To work around this, you have 3 options:

  • Add the two methods
  • Make each class that extends Shape abstract
  • Have a single method that does the function of the classes that will extend Shape, and override that method in Rectangle and Ellipse, for example:

    abstract class Shape {
        // ...
        void draw(Graphics g);


    class Rectangle extends Shape {
        void draw(Graphics g) {
            // ...


    class Ellipse extends Shape {
        void draw(Graphics g) {
            // ...

And you can switch in between them, like so:

    Shape shape = new Ellipse();
    shape.draw(/* ... */);

    shape = new Rectangle();
    shape.draw(/* ... */);

Again, just an example.

How to replace case-insensitive literal substrings in Java

If you don't care about case, then you perhaps it doesn't matter if it returns all upcase:

target.toUpperCase().replace("FOO", "");

How can I get a user's media from Instagram without authenticating as a user?

The below nodejs code scrapes popular Images from an Instagram Page. The function 'ScrapeInstagramPage' takes care of post ageing effect.

var request = require('parse5');
var request = require('request');
var rp      = require('request-promise');
var $       = require('cheerio'); // Basically jQuery for node.js 
const jsdom = require("jsdom");    
const { JSDOM } = jsdom;

function ScrapeInstagramPage (args) {
    dout("ScrapeInstagramPage for username -> " + args.username);
    var query_url = '' + args.username + '/';

    var cookieString = '';

    var options = {
        url: query_url,
        method: 'GET',
        headers: {
            'x-requested-with' : 'XMLHttpRequest',
            'accept-language'  : 'en-US,en;q=0.8,pt;q=0.6,hi;q=0.4', 
            'User-Agent'       : 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36',
            'referer'          : '',
            'Cookie'           : cookieString,
            'Accept'           : '*/*',
            'Connection'       : 'keep-alive',
            'authority'        : '' 

    function dout (msg) {
        if (args.debug) {

    function autoParse(body, response, resolveWithFullResponse) {
        // FIXME: The content type string could contain additional values like the charset. 
        // Consider using the `content-type` library for a robust comparison. 
        if (response.headers['content-type'] === 'application/json') {
            return JSON.parse(body);
        } else if (response.headers['content-type'] === 'text/html') {
            return $.load(body);
        } else {
            return body;

    options.transform = autoParse;

        .then(function (autoParsedBody) {
            if (args.debug) {
                console.log("Responce of 'Get first user page': ");
                console.log("Creating JSDOM from above Responce...");

            const dom = new JSDOM(autoParsedBody.html(), { runScripts: "dangerously" });
            if (args.debug) console.log(dom.window._sharedData); // full data doc form instagram for a page

            var user = dom.window._sharedData.entry_data.ProfilePage[0].user;
            if (args.debug) {
                console.log(user); // page user
                console.log(; // user ID
                console.log(user.full_name); // user full_name
                console.log(user.username); // user username
                console.log(user.followed_by.count); // user followed_by
                console.log(user.profile_pic_url_hd); // user profile pic

            if (user.is_private) {
                dout ("User account is PRIVATE");
            } else {
                dout ("User account is public");
                GetPostsFromUser(, 5000, undefined);
        .catch(function (err) {
            console.log( "ERROR: " + err );

    var pop_posts = [];
    function GetPostsFromUser (user_id, first, end_cursor) {
        var end_cursor_str = "";
        if (end_cursor != undefined) {
            end_cursor_str = '&after=' + end_cursor;

        options.url = '' 
                        + user_id + '&first=' + first + end_cursor_str;

            .then(function (autoParsedBody) {
                if (autoParsedBody.status === "ok") {
                    if (args.debug) console.log(;
                    var posts =;

                    // POSTS processing
                    if (posts.edges.length > 0) {
                        pop_posts = pop_posts.concat
                        ( {
                            var d = new Date();
                            var now_seconds = d.getTime() / 1000;

                            var seconds_since_post = now_seconds - e.node.taken_at_timestamp;
                            //console.log("seconds_since_post: " + seconds_since_post);

                            var ageing = 10; // valuses (1-10]; big value means no ageing
                            var days_since_post = Math.floor(seconds_since_post/(24*60*60));
                            var df = (Math.log(ageing+days_since_post) / (Math.log(ageing)));
                            var likes_per_day = (e.node.edge_liked_by.count / df);
                            // console.log("likes: " + e.node.edge_liked_by.count);
                            //console.log("df: " + df);
                            //console.log("likes_per_day: " + likes_per_day);
                            //return (likes_per_day > 10 * 1000);
                            var obj = {};
                            obj.url = e.node.display_url;
                            obj.likes_per_day = likes_per_day;
                            obj.days_since_post = days_since_post;
                            obj.total_likes = e.node.edge_liked_by.count;
                            return obj;

                        pop_posts.sort(function (b,a) {
                          if (a.likes_per_day < b.likes_per_day)
                            return -1;
                          if (a.likes_per_day > b.likes_per_day)
                            return 1;
                          return 0;


                        pop_posts.forEach(function (obj) {

                    if (posts.page_info.has_next_page) {
                        GetPostsFromUser(user_id, first, posts.page_info.end_cursor);
                } else {
                    console.log( "ERROR: Posts AJAX call not returned good..." );
            .catch(function (err) {
                console.log( "ERROR: " + err );

ScrapeInstagramPage ({username : "dress_blouse_designer", debug : false});

Try it here

Example: For given a URL '' one may call function

ScrapeInstagramPage ({username : "dress_blouse_designer", debug : false});

ERROR 1396 (HY000): Operation CREATE USER failed for 'jack'@'localhost'

The MySQL server is running with the --skip-grant-tables option so it cannot execute this statement

Does SVG support embedding of bitmap images?

You can use a data: URL to embed a Base64 encoded version of an image. But it's not very efficient and wouldn't recommend embedding large images. Any reason linking to another file is not feasible?

Get all directories within directory nodejs



npm i graph-fs


const {Node} = require("graph-fs");
const directory = new Node("/path/to/directory");

const names = directory.children  // <--
    .filter(node =>
    .map(directory =>;

MongoDB Aggregation: How to get total records count?

This could be work for multiple match conditions

            const query = [
                    $facet: {
                    cancelled: [
                        { $match: { orderStatus: 'Cancelled' } },
                        { $count: 'cancelled' }
                    pending: [
                        { $match: { orderStatus: 'Pending' } },
                        { $count: 'pending' }
                    total: [
                        { $match: { isActive: true } },
                        { $count: 'total' }
                    $project: {
                    cancelled: { $arrayElemAt: ['$cancelled.cancelled', 0] },
                    pending: { $arrayElemAt: ['$pending.pending', 0] },
                    total: { $arrayElemAt: ['$', 0] }
                Order.aggregate(query, (error, findRes) => {})

Elegant way to read file into byte[] array in Java

This works for me:

File file = ...;
byte[] data = new byte[(int) file.length()];
try {
    new FileInputStream(file).read(data);
} catch (Exception e) {

How to send 500 Internal Server Error error from a PHP script

PHP 5.4 has a function called http_response_code, so if you're using PHP 5.4 you can just do:


I've written a polyfill for this function (Gist) if you're running a version of PHP under 5.4.

To answer your follow-up question, the HTTP 1.1 RFC says:

The reason phrases listed here are only recommendations -- they MAY be replaced by local equivalents without affecting the protocol.

That means you can use whatever text you want (excluding carriage returns or line feeds) after the code itself, and it'll work. Generally, though, there's usually a better response code to use. For example, instead of using a 500 for no record found, you could send a 404 (not found), and for something like "conditions failed" (I'm guessing a validation error), you could send something like a 422 (unprocessable entity).

Change background color of edittext in android

one line of lazy code:

mEditText.getBackground().setColorFilter(Color.RED, PorterDuff.Mode.SRC_ATOP);

Programmatically scroll to a specific position in an Android ListView

-If you just want the list to scroll up\dawn to a specific position:


-if you want to get the position of a specific item in myListView:


-also this myListView.getVerticalScrollbarPosition(i);can helps you.

Good Luck :)

percentage of two int?

One of them has to be a float going in. One possible way of ensuring that is:

float percent = (float) n/v * 100;

Otherwise, you're doing integer division, which truncates the numbers. Also, you should be using double unless there's a good reason for the float.

The next issue you'll run into is that some of your percentages might look like 24.9999999999999% instead of 25%. This is due to precision loss in floating point representation. You'll have to decide how to deal with that, too. Options include a DecimalFormat to "fix" the formatting or BigDecimal to represent exact values.

Error: Module not specified (IntelliJ IDEA)

This is because the className value which you are passing as argument for
forName(String className) method is not found or doesn't exists, or you a re passing the wrong value as the class name. Here is also a link which could help you.



Module not specified

According to the snapshot you have provided this problem is because you have not determined the app module of your project, so I suggest you to choose the app module from configuration. For example:

enter image description here

How to use LocalBroadcastManager?

By declaring one in your AndroidManifest.xml file with the tag (also called static)

<receiver android:name=".YourBrodcastReceiverClass"  android:exported="true">
    <!-- The actions you wish to listen to, below is an example -->
    <action android:name="android.intent.action.BOOT_COMPLETED"/>

You will notice that the broadcast receiver declared above has a property of exported=”true”. This attribute tells the receiver that it can receive broadcasts from outside the scope of the application.
2. Or dynamically by registering an instance with registerReceiver (what is known as context registered)

public abstract Intent registerReceiver (BroadcastReceiver receiver, 
            IntentFilter filter);

public void onReceive(Context context, Intent intent) {
//Implement your logic here

There are three ways to send broadcasts:
The sendOrderedBroadcast method, makes sure to send broadcasts to only one receiver at a time. Each broadcast can in turn, pass along data to the one following it, or to stop the propagation of the broadcast to the receivers that follow.
The sendBroadcast is similar to the method mentioned above, with one difference. All broadcast receivers receive the message and do not depend on one another.
The LocalBroadcastManager.sendBroadcast method only sends broadcasts to receivers defined inside your application and does not exceed the scope of your application.

Easiest way to pass an AngularJS scope variable from directive to controller?

Edited on 2014/8/25: Here was where I forked it.

Thanks @anvarik.

Here is the JSFiddle. I forgot where I forked this. But this is a good example showing you the difference between = and @

<div ng-controller="MyCtrl">
    <h2>Parent Scope</h2>
    <input ng-model="foo"> <i>// Update to see how parent scope interacts with component scope</i>    
    <!-- attribute-foo binds to a DOM attribute which is always
    a string. That is why we are wrapping it in curly braces so
    that it can be interpolated. -->
    <my-component attribute-foo="{{foo}}" binding-foo="foo"
        isolated-expression-foo="updateFoo(newFoo)" >
            <strong>get:</strong> {{isolatedAttributeFoo}}
            <strong>set:</strong> <input ng-model="isolatedAttributeFoo">
            <i>// This does not update the parent scope.</i>
            <strong>get:</strong> {{isolatedBindingFoo}}
            <strong>set:</strong> <input ng-model="isolatedBindingFoo">
            <i>// This does update the parent scope.</i>
            <input ng-model="isolatedFoo">
            <button class="btn" ng-click="isolatedExpressionFoo({newFoo:isolatedFoo})">Submit</button>
            <i>// And this calls a function on the parent scope.</i>
var myModule = angular.module('myModule', [])
    .directive('myComponent', function () {
        return {
                /* NOTE: Normally I would set my attributes and bindings
                to be the same name but I wanted to delineate between
                parent and isolated scope. */                
    .controller('MyCtrl', ['$scope', function ($scope) {
        $ = 'Hello!';
        $scope.updateFoo = function (newFoo) {
            $ = newFoo;

Saving awk output to variable

variable=$(ps -ef | awk '/[p]ort 10/ {print $12}')

The [p] is a neat trick to remove the search from showing from ps

@Jeremy If you post the output of ps -ef | grep "port 10", and what you need from the line, it would be more easy to help you getting correct syntax

Move branch pointer to different commit without checkout

Honestly, I'm surprised how nobody thought about the git push command:

git push -f . <destination>:<branch>

The dot ( . ) refers the local repository, and you may need the -f option because the destination could be "behind its remote counterpart".

Although this command is used to save your changes in your server, the result is exactly the same as if moving the remote branch (<branch>) to the same commit as the local branch (<destination>)

How to use if - else structure in a batch file?

I believe you can use something such as

if ___ (

do this

) else if ___ (

do this


What is the common header format of Python files?

I strongly favour minimal file headers, by which I mean just:

  • The hashbang (#! line) if this is an executable script
  • Module docstring
  • Imports, grouped in the standard way, eg:
  import os    # standard library
  import sys

  import requests  # 3rd party packages

  from mypackage import (  # local source

ie. three groups of imports, with a single blank line between them. Within each group, imports are sorted. The final group, imports from local source, can either be absolute imports as shown, or explicit relative imports.

Everything else is a waste of time, visual space, and is actively misleading.

If you have legal disclaimers or licencing info, it goes into a separate file. It does not need to infect every source code file. Your copyright should be part of this. People should be able to find it in your LICENSE file, not random source code.

Metadata such as authorship and dates is already maintained by your source control. There is no need to add a less-detailed, erroneous, and out-of-date version of the same info in the file itself.

I don't believe there is any other data that everyone needs to put into all their source files. You may have some particular requirement to do so, but such things apply, by definition, only to you. They have no place in “general headers recommended for everyone”.

Can clearInterval() be called inside setInterval()?

Yes you can. You can even test it:

var i = 0;_x000D_
var timer = setInterval(function() {_x000D_
  if (i === 5) clearInterval(timer);_x000D_
  console.log('post-interval'); //this will still run after clearing_x000D_
}, 200);

In this example, this timer clears when i reaches 5.

Add ripple effect to my button with button background color?

Just use :


Instead of:


Don't forget to change your Button to

Setting CSS pseudo-class rules from JavaScript

In jquery you can easily set hover pseudo classes.

$(this).css("background-color", "yellow");
}, function(){
$(this).css("background-color", "pink");

A required class was missing while executing org.apache.maven.plugins:maven-war-plugin:2.1.1:war

You should add maven-resources-plugin in your pom.xml file. Deleting ~/.m2/repository does not work always.


Now build your project again. It should be successful!

Does C# support multiple inheritance?

C# does not support multiple inheritance built in.

For adding multiple inheritance to languages that does not support it, You can use twin design pattern

"find: paths must precede expression:" How do I specify a recursive search that also finds files in the current directory?

What's happening is that the shell is expanding "*test.c" into a list of files. Try escaping the asterisk as:

find . -name \*test.c

ConvergenceWarning: Liblinear failed to converge, increase the number of iterations

Please incre max_iter to 10000 as default value is 1000. Possibly, increasing no. of iterations will help algorithm to converge. For me it converged and solver was -'lbfgs'

log_reg = LogisticRegression(solver='lbfgs',class_weight='balanced', max_iter=10000)

How to initialize log4j properly?

import org.apache.log4j.BasicConfigurator;

Call this method


Whoops, looks like something went wrong. Laravel 5.0

In Laravel 5.5, I had the same issue


was added to .gitignore.

So Either remove ".env" it from .gitignore file.

or add it forcefully

git add .env -f

And Deploy it. It will work.

If above does not help. Try generating the Key Again

php artisan key:generate

Angular 2 Hover event

Simply do (mouseenter) attribute in Angular2+...

In your HTML do:

<div (mouseenter)="mouseHover($event)">Hover!</div> 

and in your component do:

import { Component, OnInit } from '@angular/core';

  selector: 'component',
  templateUrl: './component.html',
  styleUrls: ['./component.scss']

export class MyComponent implements OnInit {

  mouseHover(e) {
    console.log('hovered', e);

How to return rows from left table not found in right table?

Try This

FROM first_table f LEFT JOIN second_table s ON f.key=s.key
WHERE s.key is NULL

For more please read this article : Joins in Sql Server

enter image description here

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);

Javascript - validation, numbers only

Using the form you already have:

var input = document.querySelector('form[name=myForm] #username');

input.onkeyup = function() {
    var patterns = /[^0-9]/g;
    var caretPos = this.selectionStart;

    this.value = input.value.replace(patterns, '');
    this.setSelectionRange(caretPos, caretPos);

This will delete all non-digits after the key is released.

Find value in an array

If you want find one value from array, use Array#find:

arr = [1,2,6,4,9] 
arr.find {|e| e % 3 == 0}   #=>  6

See also: {|e| e % 3 == 0} #=> [ 6, 9 ]
e.include? 6              #=> true

To find if a value exists in an Array you can also use #in? when using ActiveSupport. #in? works for any object that responds to #include?:

arr = [1, 6] arr                 #=> true

Excel: replace part of cell's string value

I know this is old but I had a similar need for this and I did not want to do the find and replace version. It turns out that you can nest the substitute method like so:

=SUBSTITUTE(SUBSTITUTE(F149, "a", " AM"), "p", " PM")

In my case, I am using excel to view a DBF file and however it was populated has times like this:


So I just made a new column and put that formula in it to convert it to the excel time format.

Global Events in Angular

There is no equivalent to $scope.emit() or $scope.broadcast() from AngularJS. EventEmitter inside of a component comes close, but as you mentioned, it will only emit an event to the immediate parent component.

In Angular, there are other alternatives which I'll try to explain below.

@Input() bindings allows the application model to be connected in a directed object graph (root to leaves). The default behavior of a component's change detector strategy is to propagate all changes to an application model for all bindings from any connected component.

Aside: There are two types of models: View Models and Application Models. An application model is connected through @Input() bindings. A view model is a just a component property (not decorated with @Input()) which is bound in the component's template.

To answer your questions:

What if I need to communicate between sibling components?

  1. Shared Application Model: Siblings can communicate through a shared application model (just like angular 1). For example, when one sibling makes a change to a model, the other sibling that has bindings to the same model is automatically updated.

  2. Component Events: Child components can emit an event to the parent component using @Output() bindings. The parent component can handle the event, and manipulate the application model or it's own view model. Changes to the Application Model are automatically propagated to all components that directly or indirectly bind to the same model.

  3. Service Events: Components can subscribe to service events. For example, two sibling components can subscribe to the same service event and respond by modifying their respective models. More on this below.

How can I communicate between a Root component and a component nested several levels deep?

  1. Shared Application Model: The application model can be passed from the Root component down to deeply nested sub-components through @Input() bindings. Changes to a model from any component will automatically propagate to all components that share the same model.
  2. Service Events: You can also move the EventEmitter to a shared service, which allows any component to inject the service and subscribe to the event. That way, a Root component can call a service method (typically mutating the model), which in turn emits an event. Several layers down, a grand-child component which has also injected the service and subscribed to the same event, can handle it. Any event handler that changes a shared Application Model, will automatically propagate to all components that depend on it. This is probably the closest equivalent to $scope.broadcast() from Angular 1. The next section describes this idea in more detail.

Example of an Observable Service that uses Service Events to Propagate Changes

Here is an example of an observable service that uses service events to propagate changes. When a TodoItem is added, the service emits an event notifying its component subscribers.

export class TodoItem {
    constructor(public name: string, public done: boolean) {
export class TodoService {
    public itemAdded$: EventEmitter<TodoItem>;
    private todoList: TodoItem[] = [];

    constructor() {
        this.itemAdded$ = new EventEmitter();

    public list(): TodoItem[] {
        return this.todoList;

    public add(item: TodoItem): void {

Here is how a root component would subscribe to the event:

export class RootComponent {
    private addedItem: TodoItem;
    constructor(todoService: TodoService) {
        todoService.itemAdded$.subscribe(item => this.onItemAdded(item));

    private onItemAdded(item: TodoItem): void {
        // do something with added item
        this.addedItem = item;

A child component nested several levels deep would subscribe to the event in the same way:

export class GrandChildComponent {
    private addedItem: TodoItem;
    constructor(todoService: TodoService) {
        todoService.itemAdded$.subscribe(item => this.onItemAdded(item));

    private onItemAdded(item: TodoItem): void {
        // do something with added item
        this.addedItem = item;

Here is the component that calls the service to trigger the event (it can reside anywhere in the component tree):

    selector: 'todo-list',
    template: `
            <li *ngFor="#item of model"> {{ }}
        <br />
        Add Item <input type="text" #txt /> <button (click)="add(txt.value); txt.value='';">Add</button>
export class TriggeringComponent{
    private model: TodoItem[];

    constructor(private todoService: TodoService) {
        this.model = todoService.list();

    add(value: string) {
        this.todoService.add(new TodoItem(value, false));

Reference: Change Detection in Angular

Could not find a part of the path ... bin\roslyn\csc.exe

I had the same problem when installing my application on the server when everything worked perfectly on localhost.

None of these solutions woorked, I always had the same error:

Could not find a part of the path 'C:\inetpub\wwwroot\myApp\bin\roslyn\csc.exe'

I ended up doing this:

  • on my setup project, right clic, view > file system
  • create a bin/roslyn folder
  • select add > files and add all files from packages\Microsoft.Net.Compilers.1.3.2\tools

This solved my problem.

jQuery autocomplete with callback ajax json

My issue was that end users would start typing in a textbox and receive autocomplete (ACP) suggestions and update the calling control if a suggestion was selected as the ACP is designed by default. However, I also needed to update multiple other controls (textboxes, DropDowns, etc...) with data specific to the end user's selection. I have been trying to figure out an elegant solution to the issue and I feel the one I developed is worth sharing and hopefully will save you at least some time.

WebMethod (SampleWM.aspx):


    • To capture SQL Server Stored Procedure results and return them as a JSON String to the AJAX Caller
  • NOTES:

    • Data.GetDataTableFromSP() - Is a custom function that returns a DataTable from the results of a Stored Procedure
    • < System.Web.Services.WebMethod(EnableSession:=True) > _
    • Public Shared Function GetAutoCompleteData(ByVal QueryFilterAs String) As String

 //Call to custom function to return SP results as a DataTable
 // DataTable will consist of Field0 - Field5
 Dim params As ArrayList = New ArrayList
 params.Add("@QueryFilter|" & QueryFilter)
 Dim dt As DataTable = Data.GetDataTableFromSP("AutoComplete", params, [ConnStr])

 //Create a StringBuilder Obj to hold the JSON 
 //IE: [{"Field0":"0","Field1":"Test","Field2":"Jason","Field3":"Smith","Field4":"32","Field5":"888-555-1212"},{"Field0":"1","Field1":"Test2","Field2":"Jane","Field3":"Doe","Field4":"25","Field5":"888-555-1414"}]
 Dim jStr As StringBuilder = New StringBuilder

 //Loop the DataTable and convert row into JSON String
 If dt.Rows.Count > 0 Then
      Dim RowCnt As Integer = 1
      For Each r As DataRow In dt.Rows
           Dim ColCnt As Integer = 0
           For Each c As DataColumn In dt.Columns
               If ColCnt = 0 Then
                   jStr.Append("""" & c.ColumnName & """:""" & r(c.ColumnName) & """")
                   jStr.Append(",""" & c.ColumnName & """:""" & r(c.ColumnName) & """")
                End If
                ColCnt += 1

            If Not RowCnt = dt.Rows.Count Then
            End If

            RowCnt += 1

    End If

    //Return JSON to WebMethod Caller
    Return jStr.ToString

AutoComplete jQuery (AutoComplete.aspx):

    • Perform the Ajax Request to the WebMethod and then handle the response

    $(function() {
            source: function (request, response) {
                    type: "POST",
                    contentType: "application/json; charset=utf-8",
                    url: "SampleWM.aspx/GetAutoCompleteData",
                    dataType: "json",
                    data:'{QueryFilter: "' + request.term  + '"}',
                    success: function (data) {
                        response($.map($.parseJSON(data.d), function (item) {                                
                            var AC = new Object();

                            //autocomplete default values REQUIRED
                            AC.label = item.Field0;
                            AC.value = item.Field1;

                            //extend values
                            AC.FirstName = item.Field2;
                            AC.LastName = item.Field3;
                            AC.Age = item.Field4;
                            AC.Phone = item.Field5;

                            return AC
            minLength: 3,
            select: function (event, ui) {                    

Node.js Error: Cannot find module express

Have you tried

npm install

If you're specifically looking for just express

npm install --save express

How to add hamburger menu in bootstrap

CSS only (no icon sets) Codepen

.nav-link #navBars {_x000D_
margin-top: -3px;_x000D_
padding: 8px 15px 3px;_x000D_
border: 1px solid rgba(0,0,0,.125);_x000D_
border-radius: .25rem;_x000D_
.nav-link #navBars input {_x000D_
display: none;_x000D_
.nav-link #navBars span {_x000D_
position: relative;_x000D_
z-index: 1;_x000D_
display: block;_x000D_
margin-bottom: 6px;_x000D_
width: 24px;_x000D_
height: 2px;_x000D_
background-color: rgba(125, 125, 126, 1);_x000D_
border-radius: .25rem;_x000D_
<link href="" rel="stylesheet"/>_x000D_
<nav class="navbar navbar-expand-lg navbar-light bg-light">_x000D_
   <!-- <a class="navbar-brand" href="#">_x000D_
      <img src="" width="30" height="30" class="d-inline-block align-top" alt="">_x000D_
      </a> -->_x000D_
   <!-- -->_x000D_
   <a class="nav-link" href="#">_x000D_
      <div id="navBars">_x000D_
         <input type="checkbox" /><span></span>_x000D_
   <!-- /26317679 -->_x000D_
   <div class="collapse navbar-collapse" id="navbarNav">_x000D_
      <ul class="navbar-nav">_x000D_
         <li class="nav-item active"><a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a></li>_x000D_
         <li class="nav-item"><a class="nav-link" href="#">Features</a></li>_x000D_
         <li class="nav-item"><a class="nav-link" href="#">Pricing</a></li>_x000D_
         <li class="nav-item"><a class="nav-link disabled" href="#">Disabled</a></li>_x000D_

How Does Modulus Divison Work

The modulus operator takes a division statement and returns whatever is left over from that calculation, the "remaining" data, so to speak, such as 13 / 5 = 2. Which means, there is 3 left over, or remaining from that calculation. Why? because 2 * 5 = 10. Thus, 13 - 10 = 3.

The modulus operator does all that calculation for you, 13 % 5 = 3.

How do I escape a single quote in SQL Server?

Just insert a ' before anything to be inserted. It will be like a escape character in sqlServer

Example: When you have a field as, I'm fine. you can do: UPDATE my_table SET row ='I''m fine.';

json: cannot unmarshal object into Go value of type

Determining of root cause is not an issue since Go 1.8; field name now is shown in the error message:

json: cannot unmarshal object into Go struct field of type string

Pdf.js: rendering a pdf file using a base64 file source instead of url

from the sourcecode at

 * This is the main entry point for loading a PDF and interacting with it.
 * NOTE: If a URL is used to fetch the PDF data a standard XMLHttpRequest(XHR)
 * is used, which means it must follow the same origin rules that any XHR does
 * e.g. No cross domain requests without CORS.
 * @param {string|TypedAray|object} source Can be an url to where a PDF is
 * located, a typed array (Uint8Array) already populated with data or
 * and parameter object with the following possible fields:
 *  - url   - The URL of the PDF.
 *  - data  - A typed array with PDF data.
 *  - httpHeaders - Basic authentication headers.
 *  - password - For decrypting password-protected PDFs.
 * @return {Promise} A promise that is resolved with {PDFDocumentProxy} object.

So a standard XMLHttpRequest(XHR) is used for retrieving the document. The Problem with this is that XMLHttpRequests do not support data: uris (eg. data:application/pdf;base64,JVBERi0xLjUK...).

But there is the possibility of passing a typed Javascript Array to the function. The only thing you need to do is to convert the base64 string to a Uint8Array. You can use this function found at

var BASE64_MARKER = ';base64,';

function convertDataURIToBinary(dataURI) {
  var base64Index = dataURI.indexOf(BASE64_MARKER) + BASE64_MARKER.length;
  var base64 = dataURI.substring(base64Index);
  var raw = window.atob(base64);
  var rawLength = raw.length;
  var array = new Uint8Array(new ArrayBuffer(rawLength));

  for(var i = 0; i < rawLength; i++) {
    array[i] = raw.charCodeAt(i);
  return array;


var pdfAsDataUri = "data:application/pdf;base64,JVBERi0xLjUK..."; // shortened
var pdfAsArray = convertDataURIToBinary(pdfAsDataUri);

Math operations from string

You could use this function which is doing the same as the eval() function, but in a simple manner, using a function.

def numeric(equation):
    if '+' in equation:
        y = equation.split('+')
        x = int(y[0])+int(y[1])
    elif '-' in equation:
        y = equation.split('-')
        x = int(y[0])-int(y[1])
    return x

The right way of setting <a href=""> when it's a local file

Try swapping your colon : for a bar |. that should do it

<a href="file://C|/path/to/file/file.html">Link Anchor</a>

Executing JavaScript after X seconds

onclick = "setTimeout(function() { document.getElementById('div1').style.display='none';document.getElementById('div2').style.display='none'}, 1000)"

Change 1000 to the number of milliseconds you want to delay.

How to compare only Date without Time in DateTime types in Linq to SQL with Entity Framework?

You can try

if(dtOne.Year == dtTwo.Year && dtOne.Month == dtTwo.Month && dtOne.Day == dtTwo.Day)

How to use unicode characters in Windows command line?

I got around a similar issue deleting Unicode-named files by referring to them in the batch file by their short (8 dot 3) names.

The short names can be viewed by doing dir /x. Obviously, this only works with Unicode file names that are already known.

How to extract request http headers from a request using NodeJS connect

var host = req.headers['host']; 

The headers are stored in a JavaScript object, with the header strings as object keys.

Likewise, the user-agent header could be obtained with

var userAgent = req.headers['user-agent']; 

How to implement "confirmation" dialog in Jquery UI dialog?

Personally I see this as a recurrent requirement in many views of many ASP.Net MVC applications.

That's why I defined a model class and a partial view:

using Resources;

namespace YourNamespace.Models
  public class SyConfirmationDialogModel
    public SyConfirmationDialogModel()
      this.DialogId = "dlgconfirm";
      this.DialogTitle = Global.LblTitleConfirm;
      this.UrlAttribute = "href";
      this.ButtonConfirmText = Global.LblButtonConfirm;
      this.ButtonCancelText = Global.LblButtonCancel;

    public string DialogId { get; set; }
    public string DialogTitle { get; set; }
    public string DialogMessage { get; set; }
    public string JQueryClickSelector { get; set; }
    public string UrlAttribute { get; set; }
    public string ButtonConfirmText { get; set; }
    public string ButtonCancelText { get; set; }

And my partial view:

@using YourNamespace.Models;

@model SyConfirmationDialogModel

<div id="@Model.DialogId" title="@Model.DialogTitle">

<script type="text/javascript">
  $(function() {
      autoOpen: false,
      modal: true

    $("@Model.JQueryClickSelector").click(function (e) {
      var sTargetUrl = $(this).attr("@Model.UrlAttribute");

        buttons: {
          "@Model.ButtonConfirmText": function () {
            window.location.href = sTargetUrl;
          "@Model.ButtonCancelText": function () {


And then, every time you need it in a view, you just use @Html.Partial (in did it in section scripts so that JQuery is defined):

@Html.Partial("_ConfirmationDialog", new SyConfirmationDialogModel() { DialogMessage = Global.LblConfirmDelete, JQueryClickSelector ="a[class=SyLinkDelete]"})

The trick is to specify the JQueryClickSelector that will match the elements that need a confirmation dialog. In my case, all anchors with the class SyLinkDelete but it could be an identifier, a different class etc. For me it was a list of:

<a title="Delete" class="SyLinkDelete" href="/UserDefinedList/DeleteEntry?Params">
    <img class="SyImageDelete" alt="Delete" src="/Images/DeleteHS.png" border="0">

Write values in app.config file

Try the following:

Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);            
config.AppSettings.Settings[key].Value = value;

Multiple lines of input in <input type="text" />

If you are using React, the library can help you with:

    <InputLabel htmlFor="textContract">{`textContract`}</InputLabel>
      onChange={() => {}}

R: "Unary operator error" from multiline ggplot2 command

It's the '+' operator at the beginning of the line that trips things up (not just that you are using two '+' operators consecutively). The '+' operator can be used at the end of lines, but not at the beginning.

This works:

ggplot(, aes(x = region, y = expression, fill = species)) +

The does not:

ggplot(, aes(x = region, y = expression, fill = species))
+ geom_boxplot() 

*Error in + geom_boxplot():
invalid argument to unary operator*

You also can't use two '+' operators, which in this case you've done. But to fix this, you'll have to selectively remove those at the beginning of lines.

Add border-bottom to table row <tr>

I had a problem like this before. I don't think tr can take a border styling directly. My workaround was to style the tds in the row:

<tr class="border_bottom">


tr.border_bottom td {
  border-bottom: 1px solid black;

What is the equivalent of "none" in django templates?

{% if profile.user.first_name %} works (assuming you also don't want to accept '').

if in Python in general treats None, False, '', [], {}, ... all as false.

SQLAlchemy: print the actual query

I would like to point out that the solutions given above do not "just work" with non-trivial queries. One issue I came across were more complicated types, such as pgsql ARRAYs causing issues. I did find a solution that for me, did just work even with pgsql ARRAYs:

borrowed from:

The linked code seems to be based on an older version of SQLAlchemy. You'll get an error saying that the attribute _mapper_zero_or_none doesn't exist. Here's an updated version that will work with a newer version, you simply replace _mapper_zero_or_none with bind. Additionally, this has support for pgsql arrays:

# adapted from:
from datetime import date, timedelta
from datetime import datetime

from sqlalchemy.orm import Query

except NameError:
    basestring = str

def render_query(statement, dialect=None):
    Generate an SQL expression string with bound parameters rendered inline
    for the given SQLAlchemy statement.
    WARNING: This method of escaping is insecure, incomplete, and for debugging
    purposes only. Executing SQL statements with inline-rendered user values is
    extremely insecure.
    Based on
    if isinstance(statement, Query):
        if dialect is None:
            dialect = statement.session.bind.dialect
        statement = statement.statement
    elif dialect is None:
        dialect = statement.bind.dialect

    class LiteralCompiler(dialect.statement_compiler):

        def visit_bindparam(self, bindparam, within_columns_clause=False,
                            literal_binds=False, **kwargs):
            return self.render_literal_value(bindparam.value, bindparam.type)

        def render_array_value(self, val, item_type):
            if isinstance(val, list):
                return "{%s}" % ",".join([self.render_array_value(x, item_type) for x in val])
            return self.render_literal_value(val, item_type)

        def render_literal_value(self, value, type_):
            if isinstance(value, long):
                return str(value)
            elif isinstance(value, (basestring, date, datetime, timedelta)):
                return "'%s'" % str(value).replace("'", "''")
            elif isinstance(value, list):
                return "'{%s}'" % (",".join([self.render_array_value(x, type_.item_type) for x in value]))
            return super(LiteralCompiler, self).render_literal_value(value, type_)

    return LiteralCompiler(dialect, statement).process(statement)

Tested to two levels of nested arrays.

Determine if a String is an Integer in Java

The most naive way would be to iterate over the String and make sure all the elements are valid digits for the given radix. This is about as efficient as it could possibly get, since you must look at each element at least once. I suppose we could micro-optimize it based on the radix, but for all intents and purposes this is as good as you can expect to get.

public static boolean isInteger(String s) {
    return isInteger(s,10);

public static boolean isInteger(String s, int radix) {
    if(s.isEmpty()) return false;
    for(int i = 0; i < s.length(); i++) {
        if(i == 0 && s.charAt(i) == '-') {
            if(s.length() == 1) return false;
            else continue;
        if(Character.digit(s.charAt(i),radix) < 0) return false;
    return true;

Alternatively, you can rely on the Java library to have this. It's not exception based, and will catch just about every error condition you can think of. It will be a little more expensive (you have to create a Scanner object, which in a critically-tight loop you don't want to do. But it generally shouldn't be too much more expensive, so for day-to-day operations it should be pretty reliable.

public static boolean isInteger(String s, int radix) {
    Scanner sc = new Scanner(s.trim());
    if(!sc.hasNextInt(radix)) return false;
    // we know it starts with a valid int, now make sure
    // there's nothing left!
    return !sc.hasNext();

If best practices don't matter to you, or you want to troll the guy who does your code reviews, try this on for size:

public static boolean isInteger(String s) {
    try { 
    } catch(NumberFormatException e) { 
        return false; 
    } catch(NullPointerException e) {
        return false;
    // only got here if we didn't return false
    return true;

How to iterate through two lists in parallel?

Python 3:

import itertools as it

for foo, bar in list(it.izip_longest(list1, list2)):
    print(foo, bar)

Sqlite convert string to date

One thing you should look into is the SQLite date and time functions, especially if you're going to have to manipulate a lot of dates. It's the sane way to use dates, at the cost of changing the internal format (has to be ISO, i.e. yyyy-MM-dd).

How can I sort an ArrayList of Strings in Java?

You can use TreeSet that automatically order list values:

import java.util.Iterator;
import java.util.TreeSet;

public class TreeSetExample {

    public static void main(String[] args) {
        System.out.println("Tree Set Example!\n");

        TreeSet <String>tree = new TreeSet<String>();

        Iterator iterator;
        iterator = tree.iterator();

        System.out.print("Tree set data: ");

        //Displaying the Tree set data
        while (iterator.hasNext()){
            System.out.print( + " ");


I lastly add 'a' but last element must be 'c'.

Grep regex NOT containing string

patterns[1]="1\.2\.3\.4.*Has exploded"
patterns[2]="5\.6\.7\.8.*Has died"
patterns[3]="\!9\.10\.11\.12.*Has exploded"

for i in {1..3}
grep "${patterns[$i]}" logfile.log

should be the the same as

egrep "(1\.2\.3\.4.*Has exploded|5\.6\.7\.8.*Has died)" logfile.log | egrep -v "9\.10\.11\.12.*Has exploded"    

Python Finding Prime Factors

In case you want to use numpy here's a way to create an array of all primes not greater than n:

[ i for i in np.arange(2,n+1) if 0 not in np.array([i] * (i-2) ) % np.arange(2,i)]

Getting the exception value in Python

Another way hasn't been given yet:

except Exception, e:
    print e.message


integer division or modulo by zero

args[0] might actually not be a message.

str(e) might return the string with surrounding quotes and possibly with the leading u if unicode:

'integer division or modulo by zero'

repr(e) gives the full exception representation which is not probably what you want:

"ZeroDivisionError('integer division or modulo by zero',)"


My bad !!! It seems that BaseException.message has been deprecated from 2.6, finally, it definitely seems that there is still not a standardized way to display exception messages. So I guess the best is to do deal with e.args and str(e) depending on your needs (and possibly e.message if the lib you are using is relying on that mechanism).

For instance, with pygraphviz, e.message is the only way to display correctly the exception, using str(e) will surround the message with u''.

But with MySQLdb, the proper way to retrieve the message is e.args[1]: e.message is empty, and str(e) will display '(ERR_CODE, "ERR_MSG")'

How do I make a dotted/dashed line in Android?

I dont know why but the voted answers don't work for me. I write it this way and works good.
Define a custom view:

public class XDashedLineView extends View {

private Paint   mPaint;
private Path    mPath;
private int     vWidth;
private int     vHeight;

public XDashedLineView(Context context) {

public XDashedLineView(Context context, AttributeSet attrs) {
    super(context, attrs);

public XDashedLineView(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);

private void init() {
    mPaint = new Paint();
    mPaint.setPathEffect(new DashPathEffect(new float[] {10,10}, 0));
    mPath = new Path();

protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    this.vWidth = getMeasuredWidth();
    this.vHeight = getMeasuredHeight();
    mPath.moveTo(0, this.vHeight / 2);
    mPath.quadTo(this.vWidth / 2, this.vHeight / 2, this.vWidth, this.vHeight / 2);

protected void onDraw(Canvas canvas) {
    canvas.drawPath(mPath, mPaint);

Then you can use it in your xml:


UnicodeEncodeError: 'charmap' codec can't encode - character maps to <undefined>, print function

If you are using Windows command line to print the data, you should use

chcp 65001

This worked for me!

Put text at bottom of div

I think that's better to use flex boxes (compatibility) than the absolute position. Here's example from me in pure css.

  /*FLEX BOX */_x000D_
  display: -ms-flexbox;_x000D_
    display: -webkit-flex;_x000D_
    display: flex;_x000D_
    -webkit-flex-direction: column;_x000D_
    -ms-flex-direction: column;_x000D_
    flex-direction: column;_x000D_
    -webkit-flex-wrap: nowrap;_x000D_
    -ms-flex-wrap: nowrap;_x000D_
    flex-wrap: nowrap;_x000D_
    -webkit-justify-content: flex-start;_x000D_
    -ms-flex-pack: start;_x000D_
    justify-content: flex-start;_x000D_
    -webkit-align-content: stretch;_x000D_
    -ms-flex-line-pack: stretch;_x000D_
    align-content: stretch;_x000D_
    -webkit-align-items: flex-start;_x000D_
    -ms-flex-align: start;_x000D_
    align-items: flex-start;_x000D_
   /*FLEX BOX CHILD */_x000D_
 -webkit-order: 0;_x000D_
    -ms-flex-order: 0;_x000D_
    order: 0;_x000D_
    -webkit-flex: 0 1 auto;_x000D_
    -ms-flex: 0 1 auto;_x000D_
    flex: 0 1 auto;_x000D_
    -webkit-align-self: flex-end;_x000D_
    -ms-flex-item-align: end;_x000D_
    align-self: flex-end;_x000D_
<div class="container">_x000D_
<div class="elem1">_x000D_
  Nam pretium turpis et arcu. Sed a libero. Sed mollis, eros et ultrices tempus, mauris ipsum aliquam libero, non adipiscing dolor urna a orci._x000D_
Mauris sollicitudin fermentum libero. Pellentesque libero tortor, tincidunt et, tincidunt eget, semper nec, quam. Quisque id mi._x000D_
Donec venenatis vulputate lorem. Maecenas ullamcorper, dui et placerat feugiat, eros pede varius nisi, condimentum viverra felis nunc et lorem. Curabitur vestibulum aliquam leo._x000D_

Python ImportError: No module named wx


sudo apt-get install python-wxtools

Where to place the 'assets' folder in Android Studio?

It's simple, follow these steps

File > New > Folder > Assets Folder

Note : App must be selected before creating folder.

Adding a tooltip to an input box

If you are using bootstrap (I am using version 4.0), feel free to try the following code.

<input data-toggle="tooltip" data-placement="top" title="This is the text of the tooltip" value="44"/>

data-placement can be top, right, bottom or left

Rotate a div using javascript

To rotate a DIV we can add some CSS that, well, rotates the DIV using CSS transform rotate.

To toggle the rotation we can keep a flag, a simple variable with a boolean value that tells us what way to rotate.

var rotated = false;

document.getElementById('button').onclick = function() {
    var div = document.getElementById('div'),
        deg = rotated ? 0 : 66; = 'rotate('+deg+'deg)';    = 'rotate('+deg+'deg)';     = 'rotate('+deg+'deg)';      = 'rotate('+deg+'deg)';       = 'rotate('+deg+'deg)'; 

    rotated = !rotated;

var rotated = false;_x000D_
document.getElementById('button').onclick = function() {_x000D_
    var div = document.getElementById('div'),_x000D_
        deg = rotated ? 0 : 66;_x000D_
_x000D_ = 'rotate('+deg+'deg)'; _x000D_    = 'rotate('+deg+'deg)'; _x000D_     = 'rotate('+deg+'deg)'; _x000D_      = 'rotate('+deg+'deg)'; _x000D_       = 'rotate('+deg+'deg)'; _x000D_
    rotated = !rotated;_x000D_
#div {_x000D_
    position:relative; _x000D_
    height: 200px; _x000D_
    width: 200px; _x000D_
    margin: 30px;_x000D_
    background: red;_x000D_
<button id="button">rotate</button>_x000D_
<br /><br />_x000D_
<div id="div"></div>

To add some animation to the rotation all we have to do is add CSS transitions

div {
    -webkit-transition: all 0.5s ease-in-out;
    -moz-transition: all 0.5s ease-in-out;
    -o-transition: all 0.5s ease-in-out;
    transition: all 0.5s ease-in-out;

var rotated = false;_x000D_
document.getElementById('button').onclick = function() {_x000D_
    var div = document.getElementById('div'),_x000D_
        deg = rotated ? 0 : 66;_x000D_
_x000D_ = 'rotate('+deg+'deg)'; _x000D_    = 'rotate('+deg+'deg)'; _x000D_     = 'rotate('+deg+'deg)'; _x000D_      = 'rotate('+deg+'deg)'; _x000D_       = 'rotate('+deg+'deg)'; _x000D_
    rotated = !rotated;_x000D_
#div {_x000D_
    position:relative; _x000D_
    height: 200px; _x000D_
    width: 200px; _x000D_
    margin: 30px;_x000D_
    background: red;_x000D_
    -webkit-transition: all 0.5s ease-in-out;_x000D_
    -moz-transition: all 0.5s ease-in-out;_x000D_
    -o-transition: all 0.5s ease-in-out;_x000D_
    transition: all 0.5s ease-in-out;_x000D_
<button id="button">rotate</button>_x000D_
<br /><br />_x000D_
<div id="div"></div>

Another way to do it is using classes, and setting all the styles in a stylesheet, thus keeping them out of the javascript

document.getElementById('button').onclick = function() {

document.getElementById('button').onclick = function() {_x000D_
#div {_x000D_
    position:relative; _x000D_
    height: 200px; _x000D_
    width: 200px; _x000D_
    margin: 30px;_x000D_
    background: red;_x000D_
    -webkit-transition: all 0.5s ease-in-out;_x000D_
    -moz-transition: all 0.5s ease-in-out;_x000D_
    -o-transition: all 0.5s ease-in-out;_x000D_
    transition: all 0.5s ease-in-out;_x000D_
#div.rotated {_x000D_
    -webkit-transform : rotate(66deg); _x000D_
    -moz-transform : rotate(66deg); _x000D_
    -ms-transform : rotate(66deg); _x000D_
    -o-transform : rotate(66deg); _x000D_
    transform : rotate(66deg); _x000D_
<button id="button">rotate</button>_x000D_
<br /><br />_x000D_
<div id="div"></div>

How to add a "sleep" or "wait" to my Lua Script?

function wait(time)
    local duration = os.time() + time
    while os.time() < duration do end

This is probably one of the easiest ways to add a wait/sleep function to your script

Visual C++ executable and missing MSVCR100d.dll

I got the same error.

I was refering a VS2010 DLL in a VS2012 project.

Just recompiled the DLL on VS2012 and now everything is fine.

Moment.js get day name from date

With moment you can parse the date string you have:

var dt = moment(, "YYYY-MM-DD HH:mm:ss")

That's for UTC, you'll have to convert the time zone from that point if you so desire.

Then you can get the day of the week:


What is the regular expression to allow uppercase/lowercase (alphabetical characters), periods, spaces and dashes only?

Check out the basics of regular expressions in a tutorial. All it requires is two anchors and a repeated character class:

^[a-zA-Z ._-]*$

If you use the case-insensitive modifier, you can shorten this to

^[a-z ._-]*$

Note that the space is significant (it is just a character like any other).

GitHub - List commits by author

Just add ?author=<emailaddress> or ?author=<githubUserName> to the url when viewing the "commits" section of a repo.

ggplot2 legend to bottom and horizontal

If you want to move the position of the legend please use the following code:

library(reshape2) # for melt
df <- melt(outer(1:4, 1:4), varnames = c("X1", "X2"))
p1 <- ggplot(df, aes(X1, X2)) + geom_tile(aes(fill = value))
p1 + scale_fill_continuous(guide = guide_legend()) +

This should give you the desired result. Legend at bottom

How to add LocalDB to Visual Studio 2015 Community's SQL Server Object Explorer?

To check if LocalDb is installed or not:

  • run cmd and type in sqllocaldb i this should give you the installed sqllocaldb instances if found.
  • Run SSMS (SQL Server Management Studio).
  • Try to connect to this instance (localdb)\V11.0 using windows authentication.

If an error is raised Cannot connect to (localdb)\V11.0. change the instance name to (localdb)\MSSQLLocalDB and try again to connect, if you still get the same error.

Follow these steps to install LocalDb:

  • Close SSMS.
  • Close VS (Visual Studio) if it's running.
  • Go to Start Menu and type in search sqlLocalDb.
  • From the results that appears choose sqlLocalDb.msi and click it.
  • SQL setup will start to install LocalDB

after finishing the installation re-run SSMS and try connecting to either of the instances (localdb)\V11.0 or (localdb)\MSSQLLocalDB, one of it should work depending on what Visual Studio version you have.

You can also verify that localdb is installed using Visual Studio by simply creating new sql file and go to the connect icon on the top header of the file which by default lists all the servers you can connect to including localdb if installed.

In addition to the above mentioned ways of finding if localdb is installed, you can also use the MS windows power shell or windows command processor CMD or even NuGet package manager console on your server machine and run these commands sqllocaldb i and sqllocaldb v that will show you the localdb name if it is installed and the MSSQL server version installed and running on your machine.

Print in Landscape format

you cannot set this in javascript, you have to do this with html/css:

<style type="text/css" media="print">
  @page { size: landscape; }

EDIT: See this Question and the accepted answer for more information on browser support: Is @Page { size:landscape} obsolete?

UPDATE if exists else INSERT in SQL Server 2008

Many people will suggest you use MERGE, but I caution you against it. By default, it doesn't protect you from concurrency and race conditions any more than multiple statements, but it does introduce other dangers:

Even with this "simpler" syntax available, I still prefer this approach (error handling omitted for brevity):

UPDATE dbo.table SET ... WHERE PK = @PK;
  INSERT dbo.table(PK, ...) SELECT @PK, ...;

A lot of folks will suggest this way:

  UPDATE ...
  INSERT ...

But all this accomplishes is ensuring you may need to read the table twice to locate the row(s) to be updated. In the first sample, you will only ever need to locate the row(s) once. (In both cases, if no rows are found from the initial read, an insert occurs.)

Others will suggest this way:

  INSERT ...
  IF ERROR_NUMBER() = 2627
    UPDATE ...

However, this is problematic if for no other reason than letting SQL Server catch exceptions that you could have prevented in the first place is much more expensive, except in the rare scenario where almost every insert fails. I prove as much here:

Not sure what you think you gain by having a single statement; I don't think you gain anything. MERGE is a single statement but it still has to really perform multiple operations anyway - even though it makes you think it doesn't.

Could not open input file: artisan

First create the project from the following link to create larave 7 project: Create Project

Now you need to enter your project folder using the following command:

cd myproject

Now try to run artisan command, such as, php artisan.

Or it may happen if you didn't install compose. So if you didn't install composer then run composer install and try again artisan command.

CSS Progress Circle

What about that?


<div class="chart" id="graph" data-percent="88"></div>


var el = document.getElementById('graph'); // get canvas

var options = {
    percent:  el.getAttribute('data-percent') || 25,
    size: el.getAttribute('data-size') || 220,
    lineWidth: el.getAttribute('data-line') || 15,
    rotate: el.getAttribute('data-rotate') || 0

var canvas = document.createElement('canvas');
var span = document.createElement('span');
span.textContent = options.percent + '%';

if (typeof(G_vmlCanvasManager) !== 'undefined') {

var ctx = canvas.getContext('2d');
canvas.width = canvas.height = options.size;


ctx.translate(options.size / 2, options.size / 2); // change center
ctx.rotate((-1 / 2 + options.rotate / 180) * Math.PI); // rotate -90 deg

//imd = ctx.getImageData(0, 0, 240, 240);
var radius = (options.size - options.lineWidth) / 2;

var drawCircle = function(color, lineWidth, percent) {
        percent = Math.min(Math.max(0, percent || 1), 1);
        ctx.arc(0, 0, radius, 0, Math.PI * 2 * percent, false);
        ctx.strokeStyle = color;
        ctx.lineCap = 'round'; // butt, round or square
        ctx.lineWidth = lineWidth

drawCircle('#efefef', options.lineWidth, 100 / 100);
drawCircle('#555555', options.lineWidth, options.percent / 100);

and CSS

div {
    width:220px; height:220px;
canvas {
    display: block;
span {

Basic code was taken from Simple PIE Chart

Jquery href click - how can I fire up an event?

It doesn't because the href value is not sign_up.It is #sign_up. Try like below, You need to add "#" to indicate the id of the href value.

  alert('Sign new href executed.'); 


how to delete installed library form react native project

If you want to unlink already installed packages in react native

  1. $ react-native unlink package_name
  2. $ yarn remove package_name (if it is npm then npm uninstall --save)

If you execute 2nd step before 1st step you need to install relevant package back and execute 2nd step

Django, creating a custom 500/404 error page

From the page you referenced:

When you raise Http404 from within a view, Django will load a special view devoted to handling 404 errors. It finds it by looking for the variable handler404 in your root URLconf (and only in your root URLconf; setting handler404 anywhere else will have no effect), which is a string in Python dotted syntax – the same format the normal URLconf callbacks use. A 404 view itself has nothing special: It’s just a normal view.

So I believe you need to add something like this to your

handler404 = 'views.my_404_view'

and similar for handler500.

How to apply style classes to td classes?

Give the table a class name and then you target the td's with the following:

table.classname td {
    font-size: 90%;

CSS: how to position element in lower right?

Lets say your HTML looks something like this:

<div class="box">
    <!-- stuff -->
    <p class="bet_time">Bet 5 days ago</p>

Then, with CSS, you can make that text appear in the bottom right like so:

.box {
.bet_time {

The way this works is that absolutely positioned elements are always positioned with respect to the first relatively positioned parent element, or the window. Because we set the box's position to relative, .bet_time positions its right edge to the right edge of .box and its bottom edge to the bottom edge of .box

Detect if a page has a vertical scrollbar?

Other solutions didn't work in one of my projects and I've ending up checking overflow css property

function haveScrollbar() {
    var style = window.getComputedStyle(document.body);
    return style["overflow-y"] != "hidden";

but it will only work if scrollbar appear disappear by changing the prop it will not work if the content is equal or smaller than the window.

How to remove listview all items

Call setListAdapter() again. This time with an empty ArrayList.

Submit form and stay on same page?

The HTTP/CGI way to do this would be for your program to return an HTTP status code of 204 (No Content).

How to make a page redirect using JavaScript?

You can achieve this using the location object.

location.href = "http://someurl"; 

The POM for project is missing, no dependency information available

The scope <scope>provided</scope> gives you an opportunity to tell that the jar would be available at runtime, so do not bundle it. It does not mean that you do not need it at compile time, hence maven would try to download that.

Now I think, the below maven artifact do not exist at all. I tries searching google, but not able to find. Hence you are getting this issue.

Change groupId to <groupId>net.sourceforge.ant4x</groupId> to get the latest jar.


Another solution for this problem is:

  1. Run your own maven repo.
  2. download the jar
  3. Install the jar into the repository.
  4. Add a code in your pom.xml something like:

Where http://localhost/repo is your local repo URL:

    <-- Other repository config ... -->

Iterate over object attributes in python

The correct answer to this is that you shouldn't. If you want this type of thing either just use a dict, or you'll need to explicitly add attributes to some container. You can automate that by learning about decorators.

In particular, by the way, method1 in your example is just as good of an attribute.

Converting a list to a set changes element order

It's interesting that people always use 'real world problem' to make joke on the definition in theoretical science.

If set has order, you first need to figure out the following problems. If your list has duplicate elements, what should the order be when you turn it into a set? What is the order if we union two sets? What is the order if we intersect two sets with different order on the same elements?

Plus, set is much faster in searching for a particular key which is very good in sets operation (and that's why you need a set, but not list).

If you really care about the index, just keep it as a list. If you still want to do set operation on the elements in many lists, the simplest way is creating a dictionary for each list with the same keys in the set along with a value of list containing all the index of the key in the original list.

def indx_dic(l):
    dic = {}
    for i in range(len(l)):
        if l[i] in dic:
            dic[l[i]] = [i]

a = [1,2,3,4,5,1,3,2]
set_a  = set(a)
dic_a = indx_dic(a)

# {1: [0, 5], 2: [1, 7], 3: [2, 6], 4: [3], 5: [4]}
# {1, 2, 3, 4, 5}

How to return 2 values from a Java method?

Return an Array Of Objects

private static Object[] f () 
     double x =1.0;  
     int y= 2 ;
     return new Object[]{Double.valueOf(x),Integer.valueOf(y)};  

Vue 2 - Mutating props vue-warn

Vue.js props are not to be mutated as this is considered an Anti-Pattern in Vue.

The approach you will need to take is creating a data property on your component that references the original prop property of list

props: ['list'],
data: () {
  return {
    parsedList: JSON.parse(this.list)

Now your list structure that is passed to the component is referenced and mutated via the data property of your component :-)

If you wish to do more than just parse your list property then make use of the Vue component' computed property. This allow you to make more in depth mutations to your props.

props: ['list'],
computed: {
  filteredJSONList: () => {
    let parsedList = JSON.parse(this.list)
    let filteredList = parsedList.filter(listItem =>
    return filteredList

The example above parses your list prop and filters it down to only active list-tems, logs it out for schnitts and giggles and returns it.

note: both data & computed properties are referenced in the template the same e.g



It can be easy to think that a computed property (being a method) needs to be called... it doesn't

bootstrap responsive table content wrapping

use it in css external file.

word-wrap: break-word;
word-break: break-all;  
white-space: normal !important;
text-align: justify;

Checking whether a variable is an integer or not

# Value_Is_Int
def value_is_int(value):
        tempVal = int(value)
        return True
        return False

Call this function:

if value_is_int(value):
    print "Integer"
    print "Not integer"

SqlBulkCopy - The given value of type String from the data source cannot be converted to type money of the specified target column

Make sure that the column values u added in entity class having get set properties also in the same order which is present in target table.

Excel: Use a cell value as a parameter for a SQL query

The SQL is somewhat like the syntax of MS SQL.

SELECT * FROM [table$] WHERE *;

It is important that the table name is ended with a $ sign and the whole thing is put into brackets. As conditions you can use any value, but so far Excel didn't allow me to use what I call "SQL Apostrophes" (´), so a column title in one word is recommended.

If you have users listed in a table called "Users", and the id is in a column titled "id" and the name in a column titled "Name", your query will look like this:

SELECT Name FROM [Users$] WHERE id = 1;

Hope this helps.

How do I detect a page refresh using jquery?

if you want to bookkeep some variable before page refresh

$(window).on('beforeunload', function(){
    // your logic here

if you want o load some content base on some condition

$(window).on('load', function(){
    // your logic here`enter code here`

MySQl Error #1064

maybe you forgot to add ";" after this line of code:

`quantity` INT NOT NULL)

JavaScript moving element in the DOM

There's no need to use a library for such a trivial task:

var divs = document.getElementsByTagName("div");   // order: first, second, third
divs[2].parentNode.insertBefore(divs[2], divs[0]); // order: third, first, second
divs[2].parentNode.insertBefore(divs[2], divs[1]); // order: third, second, first

This takes account of the fact that getElementsByTagName returns a live NodeList that is automatically updated to reflect the order of the elements in the DOM as they are manipulated.

You could also use:

var divs = document.getElementsByTagName("div");   // order: first, second, third
divs[0].parentNode.appendChild(divs[0]);           // order: second, third, first
divs[1].parentNode.insertBefore(divs[0], divs[1]); // order: third, second, first

and there are various other possible permutations, if you feel like experimenting:

divs[0].parentNode.appendChild(divs[0].parentNode.replaceChild(divs[2], divs[0]));

for example :-)

Source file 'Properties\AssemblyInfo.cs' could not be found

This can also happen if you have a solution containing the project open in Visual Studio, then use your source control software to change to an older commit that does not contain that project. Normally, this would be obvious as all the project files would disappear as well. But, if it's a new project with very few or no files at all, it could be puzzling to see that just this one file, AssemblyInfo.cs, is missing. And, it's more likely you'd be messing about with an AssemblyInfo.cs when a project is new, so might miss that another file or two is also missing.

The cure is to do any of the following:

  • Fetch the missing AssemblyInfo.cs and any other missing files from another commit, taking care to manage and save your .csproj file so the referenced files don't vanish from the project—perhaps by adding and removing a random .cs file to cause changes to need to be saved (since visual studio thinks the .csproj file has been saved when it hasn't).
  • Close and reopen Visual Studio without saving (if the project file isn't really saved) or remove the project. Removing makes sense if you didn't actually want the project created yet, since it will be created in the later commit.
  • Recreate the AssemblyInfo.cs file manually. Just copy another project, and change the details, especially the GUID so it matches the one from the .sln file.

How to use a class object in C++ as a function parameter

class is a keyword that is used only* to introduce class definitions. When you declare new class instances either as local objects or as function parameters you use only the name of the class (which must be in scope) and not the keyword class itself.


class ANewType
    // ... details

This defines a new type called ANewType which is a class type.

You can then use this in function declarations:

void function(ANewType object);

You can then pass objects of type ANewType into the function. The object will be copied into the function parameter so, much like basic types, any attempt to modify the parameter will modify only the parameter in the function and won't affect the object that was originally passed in.

If you want to modify the object outside the function as indicated by the comments in your function body you would need to take the object by reference (or pointer). E.g.

void function(ANewType& object); // object passed by reference

This syntax means that any use of object in the function body refers to the actual object which was passed into the function and not a copy. All modifications will modify this object and be visible once the function has completed.

[* The class keyword is also used in template definitions, but that's a different subject.]

How to convert a column of DataTable to a List

var list = dataTable.Rows.OfType<DataRow>()
    .Select(dr => dr.Field<string>(columnName)).ToList();

[Edit: Add a reference to System.Data.DataSetExtensions to your project if this does not compile]

Angular2 http.get() ,map(), subscribe() and observable pattern - basic understanding

import { HttpClientModule } from '@angular/common/http';

The HttpClient API was introduced in the version 4.3.0. It is an evolution of the existing HTTP API and has it's own package @angular/common/http. One of the most notable changes is that now the response object is a JSON by default, so there's no need to parse it with map method anymore .Straight away we can use like below

http.get('friends.json').subscribe(result => this.result =result);

Converting xml to string using C#

As Chris suggests, you can do it like this:

public string GetXMLAsString(XmlDocument myxml)
    return myxml.OuterXml;

Or like this:

public string GetXMLAsString(XmlDocument myxml)

        StringWriter sw = new StringWriter();
        XmlTextWriter tx = new XmlTextWriter(sw);

        string str = sw.ToString();// 
        return str;

and if you really want to create a new XmlDocument then do this

XmlDocument newxmlDoc= myxml

How do I move focus to next input with jQuery?

var inputs = $('input, select, textarea').keypress(function (e) {
  if (e.which == 13) {
    var nextInput = inputs.get(inputs.index(this) + 1);
    if (nextInput) {

How do I prevent a parent's onclick event from firing when a child anchor is clicked?

To specify some sub element as unclickable write the css hierarchy as in the example below.

In this example I stop propagation to any elements (*) inside td inside tr inside a table with the class ".subtable"

   $(".subtable tr td *").click(function (event)


Closing WebSocket correctly (HTML5, Javascript)

By using close method of web socket, where you can write any function according to requirement.

var connection = new WebSocket('ws://');
    connection.onclose = () => {
            console.log('Web Socket Connection Closed');

Unix - copy contents of one directory to another

Try this:

cp Folder1/* Folder2/

Correctly ignore all files recursively under a specific folder except for a specific file type

The best answer is to add a Resources/.gitignore file under Resources containing:

# Ignore any file in this directory except for this file and *.foo files

If you are unwilling or unable to add that .gitignore file, there is an inelegant solution:

# Ignore any file but *.foo under Resources. Update this if we add deeper directories

You will need to edit that pattern if you add directories deeper than specified.

What does it mean to have an index to scalar variable error? python

IndexError: invalid index to scalar variable happens when you try to index a numpy scalar such as numpy.int64 or numpy.float64. It is very similar to TypeError: 'int' object has no attribute '__getitem__' when you try to index an int.

>>> a = np.int64(5)
>>> type(a)
<type 'numpy.int64'>
>>> a[3]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
IndexError: invalid index to scalar variable.
>>> a = 5
>>> type(a)
<type 'int'>
>>> a[3]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'int' object has no attribute '__getitem__'

How to execute an external program from within Node.js?

From the Node.js documentation:

Node provides a tri-directional popen(3) facility through the ChildProcess class.


How do I run a program from command prompt as a different user and as an admin

Runas doesn't magically run commands as an administrator, it runs them as whatever account you provide credentials for. If it's not an administrator account, runas doesn't care.

JavaScript override methods

Once should avoid emulating classical OO and use prototypical OO instead. A nice utility library for prototypical OO is traits.

Rather then overwriting methods and setting up inheritance chains (one should always favour object composition over object inheritance) you should be bundling re-usable functions into traits and creating objects with those.

Live Example

var modifyA = {
    modify: function() {
        this.x = 300;
        this.y = 400;

var modifyB = {
    modify: function() {
        this.x = 3000;
        this.y = 4000;

C = function(trait) {
    var o = Object.create(Object.prototype, Trait(trait));

    console.log("sum : " + (o.x + o.y));

    return o;


Returning pointer from a function

Allocate memory before using the pointer. If you don't allocate memory *point = 12 is undefined behavior.

int *fun()
    int *point = malloc(sizeof *point); /* Mandatory. */
    return point;

Also your printf is wrong. You need to dereference (*) the pointer.

printf("%d", *ptr);

Send XML data to webservice using php curl

Previous anwser works fine. I would just add that you dont need to specify CURLOPT_POSTFIELDS as "xmlRequest=" . $input_xml to read your $_POST. You can use file_get_contents('php://input') to get the raw post data as plain XML.

Embed Youtube video inside an Android app

It works like this:

String item = "";

String ss = "your url";
ss = ss.substring(ss.indexOf("v=") + 2);
item += ss;
DisplayMetrics metrics = getResources().getDisplayMetrics();
int w1 = (int) (metrics.widthPixels / metrics.density), h1 = w1 * 3 / 5;

try {
    "<html><body><iframe class=\"youtube-player\" type=\"text/html5\" width=\""
    + (w1 - 20)
    + "\" height=\""
    + h1
    + "\" src=\""
    + item
    + "\" frameborder=\"0\"\"allowfullscreen\"></iframe></body></html>",
                            "text/html5", "utf-8");
} catch (Exception e) {

private WebChromeClient chromeClient = new WebChromeClient() {

    public void onShowCustomView(View view, CustomViewCallback callback) {
        super.onShowCustomView(view, callback);
        if (view instanceof FrameLayout) {
            FrameLayout frame = (FrameLayout) view;
            if (frame.getFocusedChild() instanceof VideoView) {
                VideoView video = (VideoView) frame.getFocusedChild();


How to check if android checkbox is checked within its onClick method (declared in XML)?

      android:text="Fees Paid Rs100:"
      android:onClick="checkbox_clicked" />

Main Activity from here

   public class RegistA extends Activity {
CheckBox fee_checkbox;
    protected void onCreate(Bundle savedInstanceState) {
 fee_checkbox = (CheckBox)findViewById(;// Fee Payment Check box

checkbox clicked

     public void checkbox_clicked(View v)

            // true,do the task 




Where does Visual Studio look for C++ header files?

There exists a newer question what is hitting the problem better asking How do include paths work in Visual Studio?

There is getting revealed the way to do it in the newer versions of VisualStudio

  • in the current project only (as the question is set here too) as well as
  • for every new project as default

The second is the what the answer of Steve Wilkinson above explains, what is, as he supposed himself, not the what Microsoft would recommend.

To say it the shortway here: do it, but do it in the User-Directory at


in the XML-file




and not in the C:\program files - directory, where the unmodified Factory-File of Microsoft is expected to reside.

Then you do it the way as VisualStudio is doing it too and everything is regular.

For more info why to do it alike, see my answer there.

Gerrit error when Change-Id in commit messages are missing

You might be an admin doing a one-off push directly into refs/changes/<change_number>.

For example, once a commit without Change-Id landed into Subversion, you pull it out of Subversion using git-svn, and you'd like to archive it as a Gerrit patchset into a Gerrit change.

If so, you can go to project settings page (http://[installation-path]/#/admin/projects/[project-id]) and temporarily change "Require Change-Id in commit message" value to False.

Don't forget to afterwards change it back to Inherit or True!

C# HttpWebRequest The underlying connection was closed: An unexpected error occurred on a send

Enable TLs 1.2 from IE and add the following

ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;

How can I see normal print output created during pytest run?

pytest --capture=tee-sys was recently added (v5.4.0). You can capture as well as see the output on stdout/err.

SOAP or REST for Web Services?

It's nuanced.

If you need to have other systems interface with your services, than a lot of clients will be happier with SOAP, due to the layers of "verification" you have with the contracts, WSDL, and the SOAP standard.

For day-to-day systems calling into systems, I think that SOAP is a lot of unnecessary overhead when a simple HTML call will do.

How do I display image in Alert/confirm box in Javascript?

As other have mentioned you can't display an image in an alert. The solution is to show it on the webpage.

If I have my webpage paused in the debugger and I already have an image loaded, I can display it. There is no need to use jQuery; with this native 14 lines of Javascript it will work from code or the debugger command line:

function show(img){
 var _=document.getElementById('_'); 


show( myimage );

How do I remove the "extended attributes" on a file in Mac OS X?

Answer (Individual Files)

1. Showcase keys to use in selection.

xattr ~/Desktop/screenshot\ 2019-10-23\ at\ 010212.png

2. Pick a Key to delete.

xattr -d ~/Desktop/screenshot\ 2019-10-23\ at\ 010212.png
xattr -d kMDItemIsScreenCapture ~/Desktop/screenshot\ 2019-10-23\ at\ 010212.png

3. Showcase keys again to see they have been removed.

xattr -l ~/Desktop/screenshot\ 2019-10-23\ at\ 010212.png

4. Lastly, REMOVE ALL keys for a particular file

xattr -c ~/Desktop/screenshot\ 2019-10-23\ at\ 010212.png

Answer (All Files In A Directory)

1. Showcase keys to use in selection.

xattr -r ~/Desktop

2. Remove a Specific Key for EVERY FILE in a directory

xattr -rd ~/Desktop

3. Remove ALL keys on EVERY FILE in a directory

xattr -rc ~/Desktop

WARN: Once you delete these you DON'T get them back!


I wanted to address the error's people are getting. Because the errors drove me nuts too... On a mac if you install xattr in python, then your environment may have an issue.

There are two different paths on my mac for xattr

type -a xattr

    # xattr is /usr/local/bin/xattr    # PYTHON Installed Version
    # xattr is /usr/bin/xattr          # Mac OSX Installed Version

So in one of the example's where -c will not work in xargs is because in bash you default to the non-python version.

Works with -c

/usr/bin/xattr -c

Does NOT Work with -c

/usr/local/bin/xattr -c
    # option -c not recognized

My Shell/Terminal defaults to /usr/local/bin/xattr because my $PATH /usr/local/bin: is before /usr/bin: which I believe is the default.

I can prove this because, if you try to uninstall the python xattr you will see:

pip3 uninstall xattr
Uninstalling xattr-0.9.6:
  Would remove:
Proceed (y/n)?


To Fix option -c not recognized Errors.

  1. Uninstall any Python xattr you may have: pip3 uninstall xattr
  2. Close all Terminal windows & quit Terminal
  3. Reopen a new Terminal window.
  4. ReRun xattr command and it should now work.


If you want to keep the Python xattr then use


for any Shell commands in Terminal


Python's version of xattr doesn't handle images at all:

Good-Mac:~ JayRizzo$ xattr ~/Desktop/screenshot\ 2019-10-23\ at\ 010212.png
    # Traceback (most recent call last):
    #   File "/usr/local/bin/xattr", line 8, in <module>
    #     sys.exit(main())
    #   File "/usr/local/lib/python3.7/site-packages/xattr/", line 196, in main
    #     attr_value = attr_value.decode('utf-8')
    # UnicodeDecodeError: 'utf-8' codec can't decode byte 0xb0 in position 2: invalid start byte

Good-Mac:~ JayRizzo$ /usr/bin/xattr ~/Desktop/screenshot\ 2019-10-23\ at\ 010212.png

Man Pages

MAN PAGE for OSX xattr

MAN PAGE for Python xattr VERSION 0.6.4

NOTE: I could not find the python help page for current VERSION 0.9.6

Thanks for Reading!

Appending pandas dataframes generated in a for loop

you can try this.

for infile in glob.glob("*.xlsx"):
    data = pandas.read_excel(infile)

I hope it can help.

How can I break from a try/catch block without throwing an exception in Java

In this sample in catch block i change the value of counter and it will break while block:

class TestBreak {
    public static void main(String[] a) {
        int counter = 0;

        while(counter<5) {
            try {
                int x = counter/0;
            catch(Exception e) {
                counter = 1000;    

How can I update a single row in a ListView?

exactly I used this

private void updateSetTopState(int index) {
        View v = listview.getChildAt(index -

        if(v == null)

        TextView aa = (TextView) v.findViewById(;

Android: How to change CheckBox size?

I use

android:scaleX="0.70" android:scaleY="0.70"

to ajust the size of checkbox

then I set margins like this


to adjust ths location of the checkbox.

ConnectivityManager getNetworkInfo(int) deprecated

Since answers posted only allow you to query the active network, here's how to get NetworkInfo for any network, not only the active one (for example Wifi network) (sorry, Kotlin code ahead)

(getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager).run {
    allNetworks.find { getNetworkInfo(it).type == ConnectivityManager.TYPE_WIFI }?.let { network -> getNetworkInfo(network) }
//    getNetworkInfo(ConnectivityManager.TYPE_WIFI).isAvailable // This is the deprecated API pre-21

This requires API 21 or higher and the permission android.permission.ACCESS_NETWORK_STATE

How to resize a VirtualBox vmdk file

vmdk's :

  • Rather fixed size allocation (step 1,2).
  • Even after expansion, not readily available inside the vmdk's OS (step 3,4,5)


1) convert to ".vdi" first - VBoxManage clonehd v1.vmdk v1.vdi --format vdi

2) expand the size using command-line (Ref: tvial's blog for step by step info)


expand from the Virtual Media Manager in VirtualBox.


3) Expand the size of drive, with new allocation (e.g. for Ubuntu running on virtual-machine : use GParted) enter image description here enter image description here

4) Extend the filesystem - lvextend -L +50G <file-system-identifier>


$ lsblk
sda                          8:0    0   200G  0 disk 
+-sda1                       8:1    0   200G  0 part 
  +-myfs-vg-cloud          253:0    0    99G  0 lvm  /
  +-myfs-vg-swap-1         253:1    0   980M  0 lvm  [SWAP]

$ lvextend -L +100G /dev/mapper/myfs-vg-cloud

$ lsblk
sda                          8:0    0   200G  0 disk 
+-sda1                       8:1    0   200G  0 part 
  +-myfs-vg-cloud          253:0    0   199G  0 lvm  /
  +-myfs-vg-swap-1         253:1    0   980M  0 lvm  [SWAP]

5) Extend the "/home" - resize2fs <file-system-identifier>


$ df -h /home/
Filesystem                        Size  Used Avail Use% Mounted on
/dev/mapper/myfs-vg-cloud         97G   87G  6.0G  94%   /

$ resize2fs /dev/mapper/myfs-vg-cloud

$ df -h /home/
Filesystem                        Size  Used Avail Use% Mounted on
/dev/mapper/myfs-vg-cloud         196G   87G  101G  47%  /

Your system must now be ready to use, with extended allocations !!

Timestamp to human readable format

getDay() returns the day of the week. To get the date, use date.getDate(). getMonth() retrieves the month, but month is zero based, so using getMonth()+1 should give you the right month. Time value seems to be ok here, albeit the hour is 23 here (GMT+1). If you want universal values, add UTC to the methods (e.g. date.getUTCFullYear(), date.getUTCHours())

var timestamp = 1301090400,
date = new Date(timestamp * 1000),
datevalues = [
alert(datevalues); //=> [2011, 3, 25, 23, 0, 0]

Is it possible to use JS to open an HTML select to show its option list?

<select id="myDropDown">

By jQuery:

var myDropDown=$("#myDropDown");
var length = $('#myDropDown> option').length;
//open dropdown
//close dropdown

By javascript:

var myDropDown=document.getElementById("myDropDown");
var length = myDropDown.options.length;
//open dropdown
myDropDown.size = length;
//close dropdown
myDropDown.size = 0;

Copied from: Open close select

Understanding ibeacon distancing

Distances to the source of iBeacon-formatted advertisement packets are estimated from the signal path attenuation calculated by comparing the measured received signal strength to the claimed transmit power which the transmitter is supposed to encode in the advertising data.

A path loss based scheme like this is only approximate and is subject to variation with things like antenna angles, intervening objects, and presumably a noisy RF environment. In comparison, systems really designed for distance measurement (GPS, Radar, etc) rely on precise measurements of propagation time, in same cases even examining the phase of the signal.

As Jiaru points out, 160 ft is probably beyond the intended range, but that doesn't necessarily mean that a packet will never get through, only that one shouldn't expect it to work at that distance.

Find all paths between two graph nodes

I suppose you want to find 'simple' paths (a path is simple if no node appears in it more than once, except maybe the 1st and the last one).

Since the problem is NP-hard, you might want to do a variant of depth-first search.

Basically, generate all possible paths from A and check whether they end up in G.

Printing with sed or awk a line following a matching pattern

Actually sed -n '/pattern/{n;p}' filename will fail if the pattern match continuous lines:

$ seq 15 |sed -n '/1/{n;p}'

The expected answers should be:


My solution is:

$ sed -n -r 'x;/_/{x;p;x};x;/pattern/!s/.*//;/pattern/s/.*/_/;h' filename

For example:

$ seq 15 |sed -n -r 'x;/_/{x;p;x};x;/1/!s/.*//;/1/s/.*/_/;h'


  1. x;: at the beginning of each line from input, use x command to exchange the contents in pattern space & hold space.
  2. /_/{x;p;x};: if pattern space, which is the hold space actually, contains _ (this is just a indicator indicating if last line matched the pattern or not), then use x to exchange the actual content of current line to pattern space, use p to print current line, and x to recover this operation.
  3. x: recover the contents in pattern space and hold space.
  4. /pattern/!s/.*//: if current line does NOT match pattern, which means we should NOT print the NEXT following line, then use s/.*// command to delete all contents in pattern space.
  5. /pattern/s/.*/_/: if current line matches pattern, which means we should print the NEXT following line, then we need to set a indicator to tell sed to print NEXT line, so use s/.*/_/ to substitute all contents in pattern space to a _(the second command will use it to judge if last line matched the pattern or not).
  6. h: overwrite the hold space with the contents in pattern space; then, the content in hold space is ^_$ which means current line matches the pattern, or ^$, which means current line does NOT match the pattern.
  7. the fifth step and sixth step can NOT exchange, because after s/.*/_/, the pattern space can NOT match /pattern/, so the s/.*// MUST be executed!

How do I close an Android alertdialog

AlertDialog.Builder ad = new AlertDialog.Builder(this);  
ad.setTitle("Unanswered Questions");  
ad.setMessage("You have not answered all the questions.");   
ad.setPositiveButton("OK", new DialogInterface.OnClickListener() {  
   public void onClick(DialogInterface dialog, int id) {  

Can you install and run apps built on the .NET framework on a Mac?

Yes you can!

As of November 2016, Microsoft now has integrated .NET Core in it's official .NET Site

They even have a new Visual Studio app that runs on MacOS

How can I remove an element from a list, with lodash?

In Addition to @thefourtheye answer, using predicate instead of traditional anonymous functions:

  _.remove(obj.subTopics, (currentObject) => {
        return currentObject.subTopicId === stToDelete;


obj.subTopics = _.filter(obj.subTopics, (currentObject) => {
    return currentObject.subTopicId !== stToDelete;

AWS S3: how do I see how much disk space is using


Answered by Vic...

if (!class_exists('S3')) require_once 'S3.php';

// Instantiate the class
$s3 = new S3('accessKeyId', 'secretAccessKey');
S3::$useSSL = false;

// List your buckets:
echo "S3::listBuckets(): ";
echo '<pre>' . print_r($s3->listBuckets(), 1). '</pre>';

$totalSize = 0;
$objects = $s3->getBucket('name-of-your-bucket');
foreach ($objects as $name => $val) {
    // If you want to get the size of a particular directory, you can do
    // only that.
    // if (strpos($name, 'directory/sub-directory') !== false)
    $totalSize += $val['size'];

echo ($totalSize / 1024 / 1024 / 1024) . ' GB';

XAMPP - Port 80 in use by "Unable to open process" with PID 4! 12

  1. Open Task Manager (Ctrl+Alt+Delete).
  2. Go to "Details" tab.
  3. Sort by PID number.
  4. End process that is using PID number indicated in error.
  5. Restart XAMPP.

Preventing form resubmission

You need to use PRG - Post/Redirect/Get pattern and you have just implemented the P of PRG. You need to Redirect. (Now days you do not need redirection at all. See this)

PRG is a web development design pattern that prevents some duplicate form submissions which means, Submit form (Post Request 1) -> Redirect -> Get (Request 2)

Under the hood

Redirect status code - HTTP 1.0 with HTTP 302 or HTTP 1.1 with HTTP 303

An HTTP response with redirect status code will additionally provide a URL in the location header field. The user agent (e.g. a web browser) is invited by a response with this code to make a second, otherwise identical, request to the new URL specified in the location field.

The redirect status code is to ensure that in this situation, the web user's browser can safely refresh the server response without causing the initial HTTP POST request to be resubmitted.

Double Submit Problem

Double Submit Problem

Post/Redirect/Get Solution

Post/Redirect/Get Solution


htaccess "order" Deny, Allow, Deny

As Gerben suggested, just change:

order deny,allow
deny from all


order allow,deny

And the restrictions will work as you want them to.

Details can be found in Apache's docs.

How to create json by JavaScript for loop?

From what I understand of your request, this should work:

//  var status  = document.getElementsByID("uniqueID"); // this works too
var status  = document.getElementsByName("status")[0];
var jsonArr = [];

for (var i = 0; i < status.options.length; i++) {
        id: status.options[i].text,
        optionValue: status.options[i].value

open a url on click of ok button in android

create an intent and set an action for it while passing the url to the intent

yourbtn.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                String theurl = "";
                Uri urlstr = Uri.parse(theurl);
                Intent urlintent = new Intent();

Equivalent of Math.Min & Math.Max for Dates?

There is no overload for DateTime values, but you can get the long value Ticks that is what the values contain, compare them and then create a new DateTime value from the result:

new DateTime(Math.Min(Date1.Ticks, Date2.Ticks))

(Note that the DateTime structure also contains a Kind property, that is not retained in the new value. This is normally not a problem; if you compare DateTime values of different kinds the comparison doesn't make sense anyway.)

Converting int to string in C

Use snprintf, it is more portable than itoa.

itoa is not part of standard C, nor is it part of standard C++; but, a lot of compilers and associated libraries support it.

Example of sprintf

char* buffer = ... allocate a buffer ...
int value = 4564;
sprintf(buffer, "%d", value);

Example of snprintf

char buffer[10];
int value = 234452;
snprintf(buffer, 10, "%d", value);

Both functions are similar to fprintf, but output is written into an array rather than to a stream. The difference between sprintf and snprintf is that snprintf guarantees no buffer overrun by writing up to a maximum number of characters that can be stored in the buffer.

What are intent-filters in Android?

intent filter is expression which present in manifest in your app that specify the type of intents that the component is to receive. If component does not have any intent filter it can receive explicit intent. If component with filter then receive both implicit and explicit intent

Put a Delay in Javascript

Unfortunately, setTimeout() is the only reliable way (not the only way, but the only reliable way) to pause the execution of the script without blocking the UI.

It's not that hard to use actually, instead of writing this:

var x = 1;

// Place mysterious code that blocks the thread for 100 ms.

x = x * 3 + 2;
var y = x / 2;

you use setTimeout() to rewrite it this way:

var x = 1;
var y = null; // To keep under proper scope

setTimeout(function() {
    x = x * 3 + 2;
    y = x / 2;
}, 100);

I understand that using setTimeout() involves more thought than a desirable sleep() function, but unfortunately the later doesn't exist. Many workarounds are there to try to implement such functions. Some using busy loops:

function sleep(milliseconds) {
  var start = new Date().getTime();
  for (var i = 0; i < 1e7; i++) {
    if ((new Date().getTime() - start) > milliseconds){

others using an XMLHttpRequest tied with a server script that sleeps for a amount of time before returning a result.

Unfortunately, those are workarounds and are likely to cause other problems (such as freezing browsers). It is recommended to simply stick with the recommended way, which is setTimeout()).

Moving from position A to position B slowly with animation

I don't understand why other answers are about relative coordinates change, not absolute like OP asked in title.

$("#Friends").animate( {top:
  "-=" + (parseInt($("#Friends").css("top")) - 100) + "px"
} );

Angular HTML binding

Just to post a little addition to all the great answers so far: If you are using [innerHTML] to render Angular components and are bummed about it not working like me, have a look at the ngx-dynamic-hooks library that I wrote to address this very issue.

With it, you can load components from dynamic strings/html without compromising security. It actually uses Angular's DOMSanitizer just like [innerHTML] does as well, but retains the ability to load components (in a safe manner).

See it in action in this Stackblitz.

How can I get a random number in Kotlin?

Building off of @s1m0nw1 excellent answer I made the following changes.

  1. (0..n) implies inclusive in Kotlin
  2. (0 until n) implies exclusive in Kotlin
  3. Use a singleton object for the Random instance (optional)


private object RandomRangeSingleton : Random()

fun ClosedRange<Int>.random() = RandomRangeSingleton.nextInt((endInclusive + 1) - start) + start

Test Case:

fun testRandom() {
                (0..1000).all {
                (0..1000).all {
                    (0..4).contains((0 until 5).random())
                (0..1000).all {

How to emulate a do-while loop in Python?

See if this helps :

Set a flag inside the exception handler and check it before working on the s.

flagBreak = false;
while True :

    if flagBreak : break

    if s :
        print s
    try :
        s =
    except StopIteration :
        flagBreak = true

print "done"

Merge/flatten an array of arrays

I originally thought to use the .reduce method and recursively call a function to flatten inner arrays, however this can lead to stack overflows when you are working with a deeply nested array of deeply nested arrays. Using concat is also not the best way to go, because each iteration will create a new shallow copy of the array. What we can do instead is this:

const flatten = arr => {
    for(let i = 0; i < arr.length;) {
        const val = arr[i];
        if(Array.isArray(val)) {
            arr.splice(i, 1, ...val);
        } else {
            i ++;
    return arr;

We are not creating new arrays via concat and we are not recursively calling any functions.,console

ImportError: No module named requests

if you want request import on windows:

pip install request

then beautifulsoup4 for:

pip3 install beautifulsoup4

Find a value anywhere in a database

If you need to run such search only once then you can probably go with any of the scripts already shown in other answers. But otherwise, I’d recommend using ApexSQL Search for this. It’s a free SSMS addin and it really saved me a lot of time.

Before running any of the scripts you should customize it based on the data type you want to search. If you know you are searching for datetime column then there is no need to search through nvarchar columns. This will speed up all of the queries above.

" app-release.apk" how to change this default generated apk name

Yes we can change that but with some more attention


Now add this in your build.gradle in your project while make sure you have checked the build variant of your project like release or Debug so here I have set my build variant as release but you may select as Debug as well.

    buildTypes {
            release {
                minifyEnabled false
                proguardFiles getDefaultProguardFile('proguard-android.txt'), ''
                signingConfig getSigningConfig()
                applicationVariants.all { variant ->
                    variant.outputs.each { output ->
                        def date = new Date();
                        def formattedDate = date.format('yyyyMMddHHmmss')
                        output.outputFile = new File(output.outputFile.parent,
                      "-release", "-" + formattedDate)
    //for Debug use output.outputFile = new File(output.outputFile.parent,
   //                   "-debug", "-" + formattedDate)

You may Do it With different Approach Like this

 defaultConfig {
        applicationId "com.myapp.status"
        minSdkVersion 16
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"
        setProperty("archivesBaseName", "COMU-$versionName")

Using Set property method in build.gradle and Don't forget to sync the gradle before running the projects Hope It will solve your problem :)

A New approach to handle this added recently by google update You may now rename your build according to flavor or Variant output //Below source is from developer android documentation For more details follow the above documentation link
Using the Variant API to manipulate variant outputs is broken with the new plugin. It still works for simple tasks, such as changing the APK name during build time, as shown below:

// If you use each() to iterate through the variant objects,
// you need to start using all(). That's because each() iterates
// through only the objects that already exist during configuration time—
// but those object don't exist at configuration time with the new model.
// However, all() adapts to the new model by picking up object as they are
// added during execution.
android.applicationVariants.all { variant ->
    variant.outputs.all {
        outputFileName = "${}-${variant.versionName}.apk"

Renaming .aab bundle This is nicely answered by David Medenjak

tasks.whenTaskAdded { task ->
    if ("bundle")) {
        def renameTaskName = "rename${}Aab"
        def flavor ="bundle".length()).uncapitalize()
        tasks.create(renameTaskName, Copy) {
            def path = "${buildDir}/outputs/bundle/${flavor}/"
            include "app.aab"
            destinationDir file("${buildDir}/outputs/renamedBundle/")
            rename "app.aab", "${flavor}.aab"

//@credit to David Medenjak for this block of code

Is there need of above code

What I have observed in the latest version of the android studio 3.3.1

The rename of .aab bundle is done by the previous code there don't require any task rename at all.

Hope it will help you guys. :)

Java substring: 'string index out of range'

You really need to check if the string's length is greater to or equal to 38.

Symfony 2 EntityManager injection in service

Note as of Symfony 3.3 EntityManager is depreciated. Use EntityManagerInterface instead.

namespace AppBundle\Service;

use Doctrine\ORM\EntityManagerInterface;

class Someclass {
    protected $em;

    public function __construct(EntityManagerInterface $entityManager)
        $this->em = $entityManager;

    public function somefunction() {
        $em = $this->em;

Objective-C ARC: strong vs retain and weak vs assign

To understand Strong and Weak reference consider below example, suppose we have method named as displayLocalVariable.

     NSString myName = @"ABC";
     NSLog(@"My name is = %@", myName);

In above method scope of myName variable is limited to displayLocalVariable method, once the method gets finished myName variable which is holding the string "ABC" will get deallocated from the memory.

Now what if we want to hold the myName variable value throughout our view controller life cycle. For this we can create the property named as username which will have Strong reference to the variable myName(see self.username = myName; in below code), as below,

@interface LoginViewController ()

@property(nonatomic,strong) NSString* username;
@property(nonatomic,weak) NSString* dummyName;

- (void)displayLocalVariable;


@implementation LoginViewController

- (void)viewDidLoad
    [super viewDidLoad];


     [self displayLocalVariable];

- (void)displayLocalVariable
   NSString myName = @"ABC";
   NSLog(@"My name is = %@", myName);
   self.username = myName;

- (void)didReceiveMemoryWarning
    [super didReceiveMemoryWarning];


Now in above code you can see myName has been assigned to self.username and self.username is having a strong reference(as we declared in interface using @property) to myName(indirectly it's having Strong reference to "ABC" string). Hence String myName will not get deallocated from memory till self.username is alive.

  • Weak reference

Now consider assigning myName to dummyName which is a Weak reference, self.dummyName = myName; Unlike Strong reference Weak will hold the myName only till there is Strong reference to myName. See below code to understand Weak reference,

     NSString myName = @"ABC";
     NSLog(@"My name is = %@", myName);
     self.dummyName = myName;

In above code there is Weak reference to myName(i.e. self.dummyName is having Weak reference to myName) but there is no Strong reference to myName, hence self.dummyName will not be able to hold the myName value.

Now again consider the below code,

         NSString myName = @"ABC";
         NSLog(@"My name is = %@", myName);
         self.username = myName;
         self.dummyName = myName;

In above code self.username has a Strong reference to myName, hence self.dummyName will now have a value of myName even after method ends since myName has a Strong reference associated with it.

Now whenever we make a Strong reference to a variable it's retain count get increased by one and the variable will not get deallocated retain count reaches to 0.

Hope this helps.

Autowiring two beans implementing same interface - how to set default bean to autowire?

I'd suggest marking the Hibernate DAO class with @Primary, i.e. (assuming you used @Repository on HibernateDeviceDao):

public class HibernateDeviceDao implements DeviceDao

This way it will be selected as the default autowire candididate, with no need to autowire-candidate on the other bean.

Also, rather than using @Autowired @Qualifier, I find it more elegant to use @Resource for picking specific beans, i.e.

DeviceDao deviceDao;

How to view DLL functions?

Use the free DLL Export Viewer, it is very easy to use.