继承

通过 extends 实现类的继承。

class Parent {
      constructor(name,age){
        this.name = name;
        this.age =age;
      }
      breath(){
        console.log("呼呀，吸呀！")
      }
}

class Son extends Parent{
      constructor(name,age,weight){
        super(name,age);
        // 调用父亲的构造函数
        this.weight = weight;
      }
      work(){
        console.log("搬砖再搬砖");
      }
    }

var s = new Son("小木", 18,20)
s.breath();
// 呼呀，吸呀！
s.work();
// 搬砖再搬砖