基于构造函数+原型链的继承

    1. <!DOCTYPE html>
    2. <html lang="en">
    3. <head>
    4.     <meta charset="UTF-8">
    5.     <meta http-equiv="X-UA-Compatible" content="IE=edge">
    6.     <meta name="viewport" content="width=device-width, initial-scale=1.0">
    7.     <title>Document</title>
    8. </head>
    9. <body>
    10.     <script>
    11.         // 父类
    12.         function Father(uname,age){
    13.             this.uname = uname;
    14.             this.age = age;
    15.             // this指向 Father实例出来的对象
    16.         }
    18.         Father.prototype = {
    19.             constructor:Father,
    20.             eat:function(){
    21.                 console.log('吃饭');
    22.             },
    23.             speak:function(){
    24.                 console.log('说话');
    25.             }
    26.         }
    28.         // 子类
    29.         function Son(uname,age,like,weight){
    31.             // (1)利用 call 方法，改变Father构造函数内的this指向，从而实现属性的继承。
    32.             Father.call(this,uname,age);
    34.             this.like = like;
    35.             this.weight = weight;
    36.         }
    38.         // (2)让 Son.prototype.__proto__ 指向 Father.prototype,就可以实现方法的继承
    39.         Son.prototype = new Father();
    40.         Son.prototype.constructor = Son;
    42.         // 扩展子类的方法
    43.         Son.prototype.skill = function(){
    44.             console.log('我会计算机');
    45.         }
    48.         var son1 = new Son('jon',18,['玩游戏','运动'],'70kg')
    49.         son1.speak();
    51.     </script>
    52. </body>
    53. </html>