JavaScript为对象原型prototype添加属性的两种方式

复制代码 代码如下:

  <script type="text/javascript">

  <!--

  /*

  给原型 prototype 添加属性的两种方式

  */

  //方式一

  var myObj = function(){

  this.study = "JavaScript";

  }

  myObj.prototype.hobby = function()

  {

  this.hobby = "See girl";

  }

  var newObj = new myObj();

  for ( var attr in newObj )

  {

  document.write( attr +"<br/>" );

  }

  document.write( "==================== <br/>" );

  //方式二

  var superObj = { name:"xugang" };

  var subObj = { age:20 };

  function extend(superObj,subObj){

  //获得父对象的原型对象

  subObj.getSuper = superObj.prototype;

  //将父对象的属性给子对象

  for(var i in superObj){

  subObj[i] = superObj[i];

  }

  }

  extend(superObj,subObj);

  for ( var s in subObj )

  {

  document.write( s +"<br/>" ); //遍历子对象的属性

  }

  //-->

  </script>

  运行结果:

  hobby

  study

  ====================

  age

  getSuper

  name