说明：  prototype.js开发手册 Prototype.js+1.6.0.3中文参考手册chm javascript本身不是一个面向对象的脚本语言,但是可以通过prototype属性可以绑定function，从而实现一个关键字绑定多个方法和属性，通过new+关键字名可以实现面向对象编程
(prototype.js Development Manual Prototype.js+1.6.0.3 Reference Manual chm javascript itself is not an object-oriented scripting language, but can be bound through the prototype property of function, in order to achieve more than a keyword binding methods and properties, keyword names by new+ object-oriented programming can be achieved)