//繼承
function Person(name,sex)
{
 this.name=name;
 this.sex=sex;
}
Person.prototype.sayName=function()
{
 alert(this.name);
}
Person.prototype.saySex=function()
{
 alert(this.sex);
}
function Worker(name,sex,job)
{
 //繼承person類 
 Person.call(this,name,sex) //這里的this指的是Worker類的實(shí)例，如下面的'W' ,把W傳入Person構(gòu)造函數(shù)，這時(shí)W偽裝成Person構(gòu)造函數(shù)里的this
 this.job=job;
}
//Worker.prototype=Person.prototype;//如果這樣負(fù)值原型，子類的sayJob方法Person父類也會(huì)有sayJob方法，因?yàn)槭且脗鬟f
//改成如下方式則子類不會(huì)影響父類：
for(var i in Person.prototype)
{
 Worker.prototype[i]=Person.prototype[i];
}
Worker.prototype.sayJob=function()
{
 alert(this.job);
}
var p=new Person('lisi','男');
//alert(p.sayJob);
var w=new Worker('zhangsan','男','打醬油的');
w.sayName();
w.saySex();
w.sayJob();