JS 类和继承

Posted 2022-03-10 413xiaol

function User(name, pass) 
    this.name = name
    this.pass = pass

User.prototype.showName = function () 
    console.log(this.name)

User.prototype.showPass = function () 
    console.log(this.pass)



function VipUser(name, pass, level)
	User.call(this, name, pass)
	this.level = level

VipUser.prototype = new User()
VipUser.prototype.constructor=VipUser

VipUser.prototype.showLevel = function()
	console.log(this.level)



var u1 = new User(‘u1‘, ‘123‘)
u1.showName()
u1.showPass()

var v1 = new VipUser(‘v1‘, ‘123‘, ‘1‘)
v1.showName()
v1.showPass()
v1.showLevel()

console.log(v1 instanceof User);
console.log(v1 instanceof VipUser);
console.log(u1 instanceof User);
console.log(u1 instanceof VipUser);

　　

ES6中

 

class User 
    constructor(name, pass) 
        this.name = name
        this.pass = pass
    

    showName() 
        console.log(this.name)
    
    showPass() 
        console.log(this.pass)
    


class VipUser extends User 
    constructor(name, pass, level) 
        super(name, pass)
        this.level = level
    
    showLevel()
        console.log(this.level)
    


var u1 = new User(‘u1‘, ‘123‘)
u1.showName()
u1.showPass()

var v1 = new VipUser(‘v1‘, ‘123‘, ‘1‘)
v1.showName()
v1.showPass()
v1.showLevel()

console.log(v1 instanceof User);
console.log(v1 instanceof VipUser);
console.log(u1 instanceof User);
console.log(u1 instanceof VipUser);