Common writing methods and calling methods of js functions

Written in front: This article introduces in detail the common writing methods and calling methods of 5 js functions. When I usually look at other people’s code, I always see various How to write js functions in different styles. I was confused, so I found some information and made a summary. Friends who need it can take a look and use it as a reference.
1. Conventional writing method (the most common one)

//函数的写法function run () {
        alert('常规写法');//这里是你函数的内容
    } // 调用
    run();

2. Anonymous function writing method (can be thought of as assigning a function to a variable)

   // 匿名函数的写法var run = function(){
        alert('这是一种声明函数的方式，左边是一个变量，右边是一个函数的表达式，意思就是把一个匿名的函数表达式赋值给了变量myfun，只是声明了一个变量指向了一个函数对象。');//这里是你函数的内容
    }  // 调用  
    run();

3. Treat the method as an object

　// 作为对象方法，函数写法，这里创建了两个函数外面用{}包裹起来
    var Test = {
run1:function(){
  alert('这个必须放在一个对象内部，放在外边会出错！');//这里是你函数的内容}
,run2:function(){
  alert('这个必须放在一个对象内部，放在外边会出错！');//这里是你函数的内容}
}//调用Test.run1();//调用第1个函数Test.run2();//调用第2个函数

4. Add methods to the object in the constructor
Every object in javascript There is a prototype attribute. The explanation of the prototype attribute of an object in Javascript is: return a reference to the prototype of the object type.

// 给对象添加方法
    var funName = function(){};
  funName.prototype.way = function(){
        alert('这是在funName函数上的原始对象上加了一个way方法，构造函数中用到');
    }    // 调用
    var funname = new text();// 创建对象
    funname.way();//调用对象属性

5. Self-executing function
I found several different writing methods for js self-executing function. Let’s put them up for everyone to see

//方法1：最前最后加括号 (function(){alert(1);}()
); 
/*这是jslint推荐的写法，好处是，能提醒阅读代码的人，这段代码是一个整体。 
例如，在有语法高亮匹配功能的编辑器里，光标在第一个左括号后时，最后一个右括号也会高亮，看代码的人一眼就可以看到这个整体。 */

//方法2：function外面加括号 (function(){alert(1);})(); 
//这种做法比方法1少了一个代码整体性的好处。

//方法3：function前面加运算符，常见的是!与void 。!function(){alert(1);}(); 
void function(){alert(2);}(); 
/*显然，加上“!”或“+”等运算符，写起来是最简单的。 
加上“void ”要敲五下键盘，但是听说有一个好处是，比加"!"少一次逻辑运算。----我只是听说，不明所以。*/

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