继承

//定义一个preson类 包含name,age两个属性
class Person{
    name:string;
    age:number;
    constructor(name:string,age:number){
        this.name=name;
        this.age=age;
    }
    sayName(){
        console.log(this.name);
    }
}
//2.student skill saySkill
// class Student{
//     name:string
//     age:number
//     skill:string;
//     constructor(name:string,age:number,skill:string){
//         this.name=name;
//         this.age=age;
//         this.skill=skill
//     }
//     saySkill():void{
//         console.log(this.skill);
//     }
// }
class Student extends Person{
    skill:string;
    //super指的是父类，只能放在子类构造方法中的第一行
    constructor(name:string,age:number,skill:string){
        super(name,age);
        this.skill=skill
    }
}
var s:Student=new Student('list',18,"vue")
console.log(s);
s.sayName()