JS Object-oriented

Most of the time we are in the process-oriented, are just the people who use the object, now learning object-oriented is to become the person to write (transform) the object. first, what is the object

• Objects: Collections of properties and methods
• Attribute: is actually a variable (but there is a attribution)
• Method: is actually a function (but there is a attribution)
• Class: A collection of objects of the same set of properties and methods

Second,

• Declared object: var obj=new object ();
• Direct volume, declares an empty object: Var obj={};
• Direct volume, JSON:

• var obj={A:"Dfsdf", B:function  () {    alert (this  . a);};

Third, newFactory mode:1, a person's class:

• functionPerson (name,sex) {//Factory mode//classes are used to create objectsvarobj={}; This. name=name; This. sex=sex; This. showname=function() {alert ( This. name);} This. showsex=function() {alert ( This. Sex);}returnobj;}

2. Do not use new to create an object for a person

• var Ben=person ("Ben", "false");

• No change in class

constructor Mode:1, a person's class:

function Person (name,sex) {// constructor mode this. name=name; this. sex=sex; this. showname=function  () {alert (this. name);} this. showsex=function  () {alert (this. sex);}}

2. Create a new person's object with new

var ben=New person ("Ben", "false");

Iv. prototype prototype

• Format: Type. prototype. properties (methods) = parameters (function functions);
• Type: can be array\object\string, etc.
• Properties: Customizable
• Function: Binds a property (method) to a variable or attribute of all corresponding types, which must be called by the

v. instanceof Judgment

• Function: Used to indicate whether an object is an instance of a particular class;
• Format: Object instanceof Class
• Object is arr1, str2, Array ... such as
• Class is an Array, Object, String ... such as

Six, the prototype chainExample: Var arr=[1,2,3];alert (Arr.index);

• Undefined is also a value
• 1. First, you will see if ARR has the index attribute on this variable.
• 2.Array this class (constructor) has no index this property
• 3.Object This class has no index this property
• 4. Return undefined and assign values to arr

Vii. Inheritance of apply && call1. Create a human: function person (name,sex) {this.name=name;   This.sex=sex;  This.showname=function () {alert (this.name); }} 2, define a worker class (see the difference between call inheritance and apply inheritance): 3, Difference:

• When you use apply, the parameter list location must correspond to:
• function person (name,age) {}
• Student (name,age, sex) {}
• When apply is passed
• Person.apply (this,arguments);
• When using call, the parameter list position may not correspond :
• function person (name,age) {}
• Student (age,name, sex) {}
• But the location corresponds to when the call is delivered .
• Person.call (This,name,age);

Note:Call, apply change this point

• Call: Parameters in order
• Apply: A second argument when an array arguments

JS Object-oriented