Tutorial by Examples: r

enclosing shortcode The enclosing shortcode allows you to embed content within your shortcode, just like BBCode if you’ve ever used that. <?php function button_shortcode( $attr, $content = null ) { return '<a href="http://twitter.com/filipstefansson" class="twitter-button&qu...

By default, WordPress does not support shortcodes within Sidebar Widgets. It only expands the shortcodes within the content of a Post, Page, or custom post type. To add shortcode support to sidebar widgets, you can install a plugin, or use the below code: add_filter( 'widget_text', 'shortcode_unaut...

When it comes to validate some rules which are not generic data validation e.g ensuring a field is required or some range of values but they are specific to your business logic then you can create your own Custom Validator. To create a custom validation attribute, you just need to inherit Validation...

Just like you handle get requests in Express with app.get method, you can use app.post method to handle post requests. But before you can handle POST requests, you will need to use the body-parser middleware. It simply parses the body of POST, PUT, DELETE and other requests. Body-Parser middleware...

In the example we will start tomcat 7 using maven plugin, optionally add user/password protection for REST end point. Also adding feature of building war. Add below section in plugin section of pom for tomcat <plugin> <groupId>org.apache.tomcat.maven</g...

In your functions.php you can register new sidebars with this code /** * Registers sidebars * * @param array Array with default or specified array values * @since 1.0.0 */ if ( function_exists( 'register_sidebar' ) ) { register_sidebar( array ( 'name' => e...

Step 1: Install Node.js The build pipeline you will be building is based in Node.js so you must ensure in the first instance that you have this installed. For instructions on how to install Node.js you can checkout the SO docs for that here Step 2: Initialise your project as an node module Open y...

It is possible to send a message or data to all avaible connections. This can be achieved by first initializing the server and then using the socket.io object to find all sockets and then emit as you normally would emit to a single socket var io = require('socket.io')(80) // 80 is the HTTP port io...

It is possible to emit a message or data to all users except the one making the request: var io = require('socket.io')(80); io.on('connection', function (socket) { socket.broadcast.emit('user connected'); });

Java Config The configuration class needs only to be a class that is on the classpath of your application and visible to your applications main class. class MyApp { public static void main(String[] args) throws Exception { AnnotationConfigApplicationContext appContext = ...

jHipster allows you to bootstrap a Spring Boot web application with a REST API back-end and a AngularJS and Twitter Bootstrap front-end. More on jHipster here: jHipster Documentation Install brew: /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/inst...

class My_Plugin() { function __construct() { add_action( 'wp_enqueue_scripts', array( $this, 'init_fe_assets' ) ); } public function init_fe_assests() { wp_enqueue_style( 'my-plugin', plugin_dir_url( __FILE__ ) . 'assets/css/frontend/plugin.css', array(), '0.0.1', true ); ...

When using instances of QML files by directly declaring them, every property creates a binding. This is explained in the above examples. This is how you dynamically create components: var component = Qt.createComponent("Popup.qml"); var popup = component.createObject(parent, {"widt...

Note: The singleton is a design pattern. But it also considered an anti-pattern. The use of a singleton should be considered carefully before use. There are usually better alternatives. The main problem with a singleton is the same as the problem with global variables. They introduce external glo...

val and var scala> val a = 123 a: Int = 123 scala> a = 456 <console>:8: error: reassignment to val a = 456 scala> var b = 123 b: Int = 123 scala> b = 321 b: Int = 321 val references are unchangeable: like a final variable in Java, once it has been initial...

Sparse indexes: These can be particularly useful for fields that are optional but which should also be unique. { "_id" : "[email protected]", "nickname" : "Johnnie" } { "_id" : "[email protected]" } { "_id" : "julia@example...

The following is an example for setting and reading cookies using the cookie-parser module: var express = require('express'); var cookieParser = require('cookie-parser'); // module for parsing cookies var app = express(); app.use(cookieParser()); app.get('/setcookie', function(req, res){ ...

In Express, you can define middlewares that can be used for checking requests or setting some headers in response. app.use(function(req, res, next){ }); // signature Example The following code adds user to the request object and pass the control to the next matching route. var express = req...

In Express, you can define unified error handler for handling errors occurred in application. Define then handler at the end of all routes and logic code. Example var express = require('express'); var app = express(); //GET /names/john app.get('/names/:name', function(req, res, next){ if...

The XML document, I will be using throughout the examples is - <a> <b>test-value</b> <d>fragment-d</d> <c-root> <d>fragment-d</d> <e>fragment-e</e> </c-root> </a> The following queries ...