js继承

//ES6的类及继承

  {
    class Test {
      constructor(obj) {
        this.name = obj.name;
      }
      action() {
        console.log('打豆豆!')
      }
    }
    class Test1 extends Test {
      constructor(obj) {
        super(obj);
        this.age = obj.age;
      }
    }
    let instance = new Test1({ name: '小米', age: '18' });
    console.log(instance);
  }
  //ES5的类和继承(构造函数模式))
  //实例的constructor指向当前对象的构造函数

es5的继承

{
    function Test(obj) {
      this.name ? this.name = obj.name : this.name = null;
      this.action = function() {
        console.log('打豆豆!');
      }
    }

    function Test1(obj) {
      // Test.apply(this, arguments)
      this.age = obj.age;
    }
    //原型链继承(父类的实例作为子类原型)
    //优点:

    //简单
    //实例是父类的实例也是子类的实例
    //缺点:

    //无法向父级传参.
    //实例丢失constructor
    //无法实现多继承
    Test1.prototype = new Test();
    Test1.prototype.constructor = Test;
    var instance = new Test1({ name: '小米1', age: '18' });
    console.log(instance)
}