没毛病吧、………………

<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>Document</title>
</head>
<body>
    <script>
         //补充代码
         function Animal(name,num){
             this.name=name;
             this.num=num;
             this.getInfo=function(){
                 alert(this.name+":"+this.num);
             }
         }
         function Cat(name,num){
             Animal.call(this,name,num)
         }
         function Dog(name,num){
             Animal.apply(this,[name,num])
         }
         
         cat=new Cat("mao",1);
         dog=new Dog("gou",2);
         cat.getInfo();
         dog.getInfo();
         
         
         
    </script>
</body>
</html>

Victor19950925 2019-05-24

源自：JS面向对象 6-8 编程练习