Javascript Object.prototype

prototype属性可以将属性和方法添加到任何对象(Number, Boolean, String 和Date等)。

注：原型(Prototype)是一个全局的属性，它可以使用在几乎所有的对象。

语法

object.prototype.name = value

实例:

这里有一个例子展示了如何使用原型(prototype)属性的属性添加到对象：

<html>
<head>
<title>User-defined objects</title>

<script type="text/javascript">

function book(title, author){
    this.title = title; 
    this.author  = author;
}
</script>
</head>
<body>
<script type="text/javascript">
   var myBook = new book("Perl", "Mohtashim");
   book.prototype.price = null;
   myBook.price = 100;
   document.write("Book title is : " + myBook.title + "<br>");
   document.write("Book author is : " + myBook.author + "<br>");
   document.write("Book price is : " + myBook.price + "<br>");
</script>
</body>
</html>

这将产生以下结果：

Book title is : Perl
Book author is : Mohtashim
Book price is : 100