javascript继承

 1 <script>
 2     function Parent(){
 3         this.name = ‘mike‘;
 4     }
 5 
 6     function Child(){
 7         this.age = 12;
 8     }
 9     Child.prototype = new Parent();//Child继承Parent，通过原型，形成链条
10 
11     var test = new Child();
12     alert(test.age);
13     alert(test.name);//得到被继承的属性
14     //继续原型链继承
15     function Brother(){   //brother构造
16         this.weight = 60;
17     }
18     Brother.prototype = new Child();//继续原型链继承
19     var brother = new Brother();
20     alert(brother.name);//继承了Parent和Child,弹出mike
21     alert(brother.age);//弹出12
22 </script>

 1 <script>
 2     function Parent(age){
 3         this.name = [‘mike‘,‘jack‘,‘smith‘];
 4         this.age = age;
 5     }
 6 
 7     function Child(age){
 8         Parent.call(this,age);
 9     }
10     var test = new Child(21);
11     alert(test.age);//21
12     alert(test.name);//mike,jack,smith
13     test.name.push(‘bill‘);
14     alert(test.name);//mike,jack,smith,bill
15 </script>

 1 <script>
 2      function obj(o){
 3          function F(){}
 4          F.prototype = o;
 5          return new F();
 6      }
 7     var box = {
 8         name : ‘trigkit4‘,
 9         arr : [‘brother‘,‘sister‘,‘baba‘]
10     };
11     var b1 = obj(box);
12     alert(b1.name);//trigkit4
13 
14     b1.name = ‘mike‘;
15     alert(b1.name);//mike
16 
17     alert(b1.arr);//brother,sister,baba
18     b1.arr.push(‘parents‘);
19     alert(b1.arr);//brother,sister,baba,parents
20 
21     var b2 = obj(box);
22     alert(b2.name);//trigkit4
23     alert(b2.arr);//brother,sister,baba,parents
24 </script>