//父类
function Person(){
this.money=1000
}
1.原型链继承
function Sam(){}
Sam.prototype = new Person();
Sam.prototype.address ='中国';
2.构造继承
function Sam(){
Person.call(this)
this.address='中国'
}
3.实例继承
function Sam(){
var instants = new Person()
instants.address='中国'
return instants
}
4.Object.create()方法继承
function Sam (){
return Object.create(new Person())
}