Differences between JS function definition methods-Basic Knowledge-js tutorial

Source: Internet
Author: User
The following is a brief introduction to the differences in JS function definition methods. I think it is quite good. Now I will share it with you for your reference. Let's take a look at it with xiaobian. There are two methods to define JS functions:

(1) typical function declaration

Function slide (arguments) {//... code}

(2) define a function in the form of a function expression

Var slide = function (arguments) {//... code}

Although the above two methods are logically equivalent, they are slightly different:

Difference 1: Functions in Example 1 will be loaded into the scope before code execution, while in example 2, they will be fixed only when the code is executed to that line;
Difference 2: The function declaration will specify a name for the function, and the function expression is to create an anonymous function, and then assign this anonymous function to a variable;

Take the following example:

Function factorial (num) {if (num <= 1) {return 1;} else {return num * arguments. callee (num-1) ;}}var anotherFactorial = factorial; factorial = null; console. log (anotherFactorial); // output factorial () {}. If a function name is defined as a function expression, var factorial = function (num ){//... code }//... codeconsole. log (anotherFactorial); // output function () {}, anonymous function

The differences between the above JS function definition methods are all the content shared by the editor. I hope you can give us a reference and support me more.

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