这里有新鲜出炉的 Javascript 教程,程序狗速度看过来!
Javascript 是一种由 Netscape 的 LiveScript 发展而来的原型化继承的基于对象的动态类型的区分大小写的客户端脚本语言,主要目的是为了解决服务器端语言,比如 Perl,遗留的速度问题,为客户提供更流畅的浏览效果。
本文主要介绍了 js 的三种继承方式。具有一定的参考价值,下面跟着小编一起来看下吧
1.js 原型(prototype)实现继承
代码如下
- <body>
- <script type="text/javascript">
- function Parent(name,age){
- this.name=name;
- this.age=age;
- this.sayHi=function(){
- alert("Hi, my name is "+this.name+", my age is "+this.age);
- }
- }
- //Child继承Parent
- function Child(grade){
- this.grade=grade;
- this.sayGrade=function(){
- alert("My grade is "+this.grade);
- }
- }
- Child.prototype=new Parent("小明","10");///////////
- var chi=new Child("5");
- chi.sayHi();
- chi.sayGrade();
- </script>
- </body>
2. 构造函数实现继承
代码如下:
- <body>
- <script type="text/javascript">
- function Parent(name,age){
- this.name=name;
- this.age=age;
- this.sayHi=function(){
- alert("Hi, my name is "+this.name+", my age is "+this.age);
- }
- }
- //Child继承Parent
- function Child(name,age,grade){
- this.grade=grade;
- this.sayHi=Parent;///////////
- this.sayHi(name,age);
- this.sayGrade=function(){
- alert("My grade is "+this.grade);
- }
- }
- var chi=new Child("小明","10","5");
- chi.sayHi();
- chi.sayGrade();
- </script>
- </body>
3.call , apply 实现继承 ----- 很方便!
代码如下:
- <body>
- <script type="text/javascript">
- function Parent(name,age){
- this.name=name;
- this.age=age;
- this.sayHi=function(){
- alert("Hi, my name is "+this.name+", my age is "+this.age);
- }
- }
- function Child(name,age,grade){
- this.grade=grade;
- // Parent.call(this,name,age);///////////
- // Parent.apply(this,[name,age]);/////////// 都可
- Parent.apply(this,arguments);///////////
- this.sayGrade=function(){
- alert("My grade is "+this.grade);
- }
- // this.sayHi=function(){
- // alert("Hi, my name is "+this.name+", my age is "+this.age+",My grade is "+this.grade);
- // }
- }
- var chi=new Child("小明","10","5");
- chi.sayHi();
- chi.sayGrade();
- </script>
- </body>
来源: http://www.phperz.com/article/17/0531/328283.html