Tutorial by Examples: ev

The CustomEvent API allows developers to create custom events and trigger them on DOM nodes, passing data along the way. event = new CustomEvent(typeArg, customEventInit); typeArg - DOMString representing the name of the event. customEventInit - is optional parameters (that will be passed as e ...

Note: this is not very efficient due to the nature of List (see Remarks below). It will be better to construct the list the "right" way from the beginning than to construct it and then reverse it. > List.reverse [1,3,5,7,9] [9,7,5,3,1] : List number

This code is to add and remove a value from a flagged enum-instance: [Flags] public enum MyEnum { Flag1 = 1 << 0, Flag2 = 1 << 1, Flag3 = 1 << 2 } var value = MyEnum.Flag1; // set additional value value |= MyEnum.Flag2; //value is now Flag1, Flag2 value...

All actions performed in a timer are handled in the "Tick" event. public partial class Form1 : Form { Timer myTimer = new Timer(); public Form1() { InitializeComponent(); myTimer.Tick += myTimer_Tick; //assign the event handler named "myT...

Given the following DataFrame: In [11]: df = pd.DataFrame(np.random.randn(6, 3), columns=['A', 'B', 'C']) In [12]: df.set_index(['A', 'B'], inplace=True) In [13]: df Out[13]: C A B 0.902764 -0.259656 -1.864541 -0.695893 0.308893 0...

The Foundation framework provides the Operation type, which represents a high-level object that encapsulates a portion of work that may be executed on a queue. Not only does the queue coordinate the performance of those operations, but you can also establish dependencies between operations, create c...

The remainder operator in Julia is the % operator. This operator behaves similarly to the % in languages such as C and C++. a % b is the signed remainder left over after dividing a by b. This operator is very useful for implementing certain algorithms, such as the following implementation of the Si...

Modify your Gemfile to include the Devise gem: gem 'devise' Then update your gems with: $ bundle install Run the installers in your project: $ rails generate devise:install Then create your Devise model (e.g. User) with: $ rails generate devise User you'll need to set up the default ...

For Facebook config.omniauth :facebook, facebook_app_id, facebook_secret_key, :display => "popup", :scope => 'email,publish_actions', info_fields: 'email,name' For Twitter config.omniauth :twitter, twitter_app_id, twitter_secret_key, :display => "popup", :scope =&gt...

The System.Web.SessionState.HttpSessionState object provides a way to persist values between HTTP requests. In the example below, a user's preference for warnings is being saved in the session. Later on, while serving another request to the user, the application can read this preference from session...

To start the process: $ forever start index.js warn: --minUptime not set. Defaulting to: 1000ms warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms info: Forever processing file: index.js List running Forever instances: $ forever list i...

First, here's what can happen when text/template is used for HTML. Note Harry's FirstName property). package main import ( "fmt" "html/template" "os" ) type Person struct { FirstName string LastName string Street string Cit...

Fetching resources over the network is both slow and expensive: the download may require multiple roundtrips between the client and server, which delays processing and may block rendering of page content, and also incurs data costs for the visitor. All server responses should specify a caching p...

Add the required network permissions to the application manifest file: <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" /> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> <uses-permission android:name="android....

Define Interface public interface ClickHandler { public void onButtonClick(User user); } Create Model class public class User { private String name; public User(String name) { this.name = name; } public String getName() { return name; } ...

By default, Shapes in Excel do not have a specific way to handle single vs. double clicks, containing only the "OnAction" property to allow you to handle clicks. However, there may be instances where your code requires you to act differently (or exclusively) on a double click. The follow...

The Never type cannot be constructed (the Basics module hasn't exported its value constructor and hasn't given you any other function that returns Never either). There is no value never : Never or a function createNever : ?? -> Never. This has its benefits: you can encode in a type system a poss...

Prevent access to your .htaccess file <Files .htaccess> order allow,deny deny from all </Files> # Rename the file AccessFileName thehtfile.ess Prevent URL attacks # Enable rewrites RewriteEngine On # Block <script> tags from executing in the URL RewriteCond %{QUE...

Rust tuples, as in most other languages, are fixed-size lists whose elements can all be of different types. // Tuples in Rust are comma-separated values or types enclosed in parentheses. let _ = ("hello", 42, true); // The type of a tuple value is a type tuple with the same number of el...

Rust programs use pattern matching extensively to deconstruct values, whether using match, if let, or deconstructing let patterns. Tuples can be deconstructed as you might expect using match fn foo(x: (&str, isize, bool)) { match x { (_, 42, _) => println!("it's 42"),...