1.

// class
class Coder{
    name(val){
        console.log(`val = ${val}`);
        return val;
    }

    skill(val){
        console.log(this.name('js') + ':' + 'Skill-' + val);
    }

    constructor(a,b){
        this.a = a;
        this.b = b;
    }

    add(){
        return this.a + this.b;
    }
}

let js = new Coder(1,2);
js.name('脚本');
js.skill('web');
console.log(js.add());

2.类的继承

// class
class Coder{
    name(val){
        console.log(`val = ${val}`);
        return val;
    }

    skill(val){
        console.log(this.name('js') + ':' + 'Skill-' + val);
    }

    constructor(a,b){
        this.a = a;
        this.b = b;
    }

    add(){
        return this.a + this.b;
    }
}

class htmler extends Coder{

}

let pang = new htmler();
pang.name('脚本');