javasrcipt中型知识点

面向对象原型继承

	类：模板
	对象：具体的实例
	在javascript中类与模板用到了极致
	原型：
	   var student={
        name:'caofeng',
       run:function (){
            console.log(this.name+"run.....");
        }
    };

   var xiaoming={
        name:'xiaoming'
    };
   //小明的原型是student
    xiaoming._proto_=student;

class 继承

class关键字实在es6引入的
定义一个类,属性和方法
 class student{
    constructor(name) {
        this.name=name;
    }
    hello(){
        alert('hello');
    }
}
let xaioming=new student("xiaoming");

继承 
    class student{
    constructor(name) {
        this.name=name;
    }
    hello(){
        alert('hello');
    }
}

class xaiostudent extends  student{
    constructor(name,grade) {
        super(name);
        this.grade=grade;


    }
    run(){
        alert(this.name+"删除跑路");
    }
}

let xaioming=new student("xiaoming");
let xioahong=new xaiostudent("xiaohong",1);