Use JAVASCRIPT to implement static objects, static methods, and static attributes

Use JAVASCRIPT to implement static objects, static methods, and static attributes

The object-oriented feature of Javascript language is very weak. When other object-oriented languages create a class, they only need to use the keyword static to specify the class as a static class. Javascript does not provide such keywords as static, to make Javascript "static" only relies on some "tricks and tricks.

The code lists two static methods/attribute implementation methods,One is static methods and attributes of static classes., The other isStatic methods and attributes of non-static classesThe code description is written in the code comments of each line, so it will not be repeated here.

/****************************************

* Method 1

* All classes, methods, and properties are static types.

* You cannot create an instance.

*****************************************/

var Time = {

    today: ‘2009-3-8′, 

    weather: ‘rain’, 

    show: function() {

alert(‘Today is ‘ + this.today); 

}

}; 

// Static objects can be used directly without the need to create an instance

alert(‘It is ‘ + Time.weather + ‘ today.’); 

Time.show(); 

// The following code will fail because the static class cannot create an instance.

//var t = new Time();

//t.show();

/****************************************

* Method 2

* Common objects with static and non-static attributes and Methods

* Instantiation can be used.

* Note:

* 1. Use the class name to access static methods/Properties

* 2. Use the Instance name to access non-static methods/attributes

*****************************************/

function Person(name) {

// Non-static attributes

this.name = name; 

// Non-static method

this.show = function() {

alert(‘My name is ‘ + this.name + ‘.’); 

}

}

// Add static attributes. All users are talking.

Person.mouth = 1; 

// Add a static method.

Person.cry = function() {

alert(‘Wa wa wa …’); 

}; 

// Use the prototype keyword to add non-static attributes. Each user may have different teeth.

Person.prototype.teeth = 32; 

// Non-static methods must be accessed through class instances

var me = new Person(‘Zhangsan’); 

// Use non-static methods and attributes

me.show(); 

alert(‘I have ‘ + me.teeth + ‘ teeth.’); 

// Use static methods and attributes

Person.cry(); 

alert(‘I have ‘ + Person.mouth + ‘ mouth.’);

//

Var p = new Person ("x"); alert (p. mouth); // undefined p. cry (); // Uncaught TypeError: Object #
 
  
Has no method 'cry'
 

It can be found that the instance object cannot have static methods and attributes of the category. Only class names are allowed for access.

function Person(name){this.name=name;this.show=function(){alert("My Name is "+this.name);};};Person.mouth=1;Person.cry=function(){alert("wa wa");}Person.prototype.teeth=32;var p=new Person("x");alert(Person["mouth"]);//1p["show"]();//My name is x

In Jquery, you can use the static methods and attributes of the object as follows:

 
var arr=new Array();arr["push"]("x");alert(arr["length"]);//1
You are welcome to further discuss and make progress together!