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1, Object methods, properties: Is the method at the object instance level, did not create an instance, this instance has the corresponding object method, the instance can use the object method.
Eg:function people (name) {
Object properties, public (that is, each instance has one of this property or method)
THIS.name = name;
Object method, Public
This.introduce = function () {
Alert (' My name = ' +this.name ');
}；
}
2, class methods, properties (static methods, properties): The function at the class level, do not need to generate an instance of the existing properties, in memory to open a copy.
Called directly using the (class name. property). Use (class name. Property = .... Create
//公有静态属性 在类的外部
//公有静态属性不能使用 【this.属性】，只能使用 【对象.属性】 调用
Eg: Connect to Person:
Person.run = function () {
Alert (' This is a static method (class method) ');
}
Person.sex = "This is a static property";
3, the prototype method: Add a property (method) to the prototype of the class, by the prototype added, in the subsequent creation of the instance is a share of the code, in memory only one copy.
( Adding this method to the prototype will enable sharing.) This makes it necessary to allocate the appropriate memory for each instance when it is initialized. )
//原型属性，当作是类内部的属性使用【this.原型属性】，也可以当成公有静态属性使用【对象.prototype.原型属性】
Use (class name. prototype. Properties = ... ) Add Create,
Called through an instance.
Eg:Person.prototype.introduceChinese = function () {
Alert (' This is the prototype method ');
}
======= I'm a split line ==============================================================================
Differences and understandings of three method attributes:
<meta http-equiv= "Content-type" content= "text/html; Charset=utf-8 ">
<title>test</title>
<body>
<script>
Object Constructors
function Atest (name) {
Private properties, which can only be used inside the object constructor
var className = "Atest";
Public property, called after an object instantiation
THIS.name = name;
Object methods
This.hello = function () {
alert (this.name);
Alert (this.msg ());//The method of extending using the prototype method can be used inside the class
alert (this.sex);//Properties extended using the prototype method can be used inside the class
alert (atest.age);//static property is called when the format is [object. Static property]
}
}
The location of the class method (which is actually called directly by a static method): The external syntax format for the Person class: Class name. Method name = function ([parameter ...]) {statement line;}
Atest.run = function () {
Alert ("I am the class method Run");
}
Prototyping methods
Atest.prototype.msg = function () {
Alert ("My name is:" +this.name);//If the prototype method is called directly as a static method, THIS.name cannot be called
}
public static properties outside of class
Atest.age = 20;//public static property cannot use "this. Property" and can only be called with "object. Properties"
The prototype property, which is considered to be a property inside the class, uses the "this. prototype attribute", or it can be used as a public static property "object. prototype. Prototype Properties"
Atest.prototype.sex = "male";
Atest.run (); Class methods are also static methods that you can use directly with the object. static method ()
Atest.prototype.msg ();//The prototype method is used as a static method when using the object. Prototype. Method () "
alert (Atest.prototype.sex);//The prototype property is used as a static property when you use the object. Prototype. Method () "
var a = new Atest ("Zhangsan");//Object methods and prototype methods need to instantiate objects before they can be used
A.hello ();//object method must instantiate object
A.msg ();//The prototype method must instantiate the object
Alert (A.age)://error, public static property can only be called with "object. Property"
PS: As far as possible the method is defined as a prototype method, the prototype method avoids each call to the constructor of the property or method construction, save space, create objects faster.
</script>
</body>
JavaScript class methods, object properties, and the relevant understanding of prototype methods
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