JavaScript prototype 属性

转载：http://www.w3school.com.cn/jsref/jsref_prototype_array.asp

prototype 属性使您有能力向对象添加属性和方法。

<script type="text/javascript">

function employee(name,job,born)
{
this.name=name;
this.job=job;
this.born=born;
}

var bill=new employee("Bill Gates","Engineer",1985);

employee.prototype.salary=null;
bill.salary=20000;

document.write(bill.salary);

</script>

输出：20000

JS中创建类，即function   此列中employee为创建的类。

var bill=new employee("Bill Gates","Engineer",1985); //实例化employee类