Introduction to JavaScript advanced syntax

(Function ($) {}) (jQuery );

In fact, it is relatively simple to understand several concepts:

1. (). In JavaScript, () indicates executing a method, for example:

Function x (){

Alert ("xxx ");

}

Var a = x; // no call. a is a function.

Var a = x (); // call the function. The value of a is the result of the call: undefined

2. jQuery is a jQuery object. It indicates that when a function is called, a parameter is input as a jQuery object.

There's nothing to say about it.

3. (function ($) {}) This is an anonymous function. The parameter is $, which is required by parentheses.

In this way, we can understand that the above formula is equivalent

Var f = function ($ ){};

F (jQuery );

Now let's take a look, that is, it's not simple or weird...