js原生继承之——构造函数式继承实例

<!DOCTYPE html>
<html lang="en">
<head>
   <meta charset="UTF-8">
   <title>constructorfunctionInherit</title>
   <script type="text/javascript">
   //声明父类
   function superClass(id){
       this.id = id;
       this.books = ['html','css','js'];
   }
   superClass.prototype.getBooks = function(){
       console.log(this.books);
   }
   //声明子类
   function subClass(id){
       superClass.call(this,id);//让子this指向父this，后面带的是父类需传入的参数id
   }
   // subClass.prototype.getSubName = function(){
   //    console.log(this.id);
   // }
   //实例化对象测试
   var test1 = new subClass(1);
   var test2 = new subClass(2);
   test2.books.push('php');//test2插入的数据'php'不影响test1

console.log(test1.id);      //1
   console.log(test1.books);   //["html", "css", "js"]
   console.log(test2.id);      //2
   console.log(test2.books);   //["html", "css", "js", "php"]
    //注：构造函数式继承是访问不到父原型链上的属性和方法的
   test1.getBooks();   //报错：undefined is not a function

//本例已经通过验证
</script>
</head>
<body>

</body>
</html>

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js原生继承之——构造函数式继承实例

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