Several good ways to define functions in js function_javascript skills

Four ways to define functions in js function

1. The most basic one is used as a basic function declaration.

Copy code The code is as follows:

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function func(){}
or
var func=function(){};

2. Use as a class constructor:

Copy the code as follows:

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function class(){}
class.prototype ={};
var item=new class();

3. Use as closure:

Copy the code as follows:

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(function(){
//Independent scope
})() ;

4. Can be used as a selector:

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var addEvent=new function(){
if(!-[1,]) return function(elem,type,func){attachEvent(elem ,'on' type,func);};
else return function(elem,type,func){addEventListener(elem,type,func,false);}
};//Avoid repeated judgment

5. Mixed application of the above four situations:

Copy code The code is as follows:

Copy code The code is as follows:

var class=new function(){
var privateArg;//static private variable
function privateMethod=function(){};//static Private method
return function(){/*real constructor*