JavaScript Iife (Instant execution method)

iife:immediately-invoked function expression

(1) standard notation

1 (function(window, document, undefined) {2     //3 }) (window, document);

For example:

1 // JQuery 2 (function($) {}) (jQuery); 3 // MUI 4 (function($) {}) (MUI);

(2) Scope scope
JavaScript has a function scope, so function first creates a private scope and creates an execution context when it executes.

1 varLogmyname =function(name) {2 Console.log (name);3 };4Logmyname (' John Doe ');5 6 varLogmyname = (function(name) {7 Console.log (name);8}) (' Harry ');9 Ten varA =!function() { One     return true; A }(); -Console.log (a);//Print output False -  the varB = (function() { -     return true; - })(); -Console.log (b);//Print Output True +  - //force JavaScript to recognize code (rarely used in this way) +!function() { A     // ...   at }(); -  -+function() { -     // ...   - }(); -  in-function() { -     // ...   to }(); +  -~function() { the     // ...   *}();

1(function($, window, document, undefined) {2     //use $ to point to jQuery, such as:3     //$ (document). addclass (' test '); 4 }) (JQuery, window, document);5 6(function(A, B, C, d) {7     //the code will be compressed to:8     //A (c). addclass (' test '); 9}) (JQuery, window, document);

Transferred from: http://rensanning.iteye.com/blog/2080429

JavaScript Iife (Instant execution method)