JavaScript中类的定义方式详解(四种方式)

工厂方式代码示例

function createCar(name,color,price){
  var tempcar=new Object;
  tempcar.name=name;
  tempcar.color=color;
  tempcar.price=price;
  tempcar.getName=function(){
   document.write(this.name+"-----"+this.color+"<br>");
  };
  return tempcar;
}
var car1=new createCar("工厂桑塔纳","red","121313");
car1.getName();

function getName(){
  document.write(this.name+"-----"+this.color+"<br>");
}

构造函数方式代码示例

function Car(name,color,price){
  this.name=name;
  this.color=color;
  this.price=price;
  this.getColor=function(){
   document.write(this.name+"-----"+this.color+"<br>");
  };
}
var car2=new Car("构造桑塔纳","red","121313");
car2.getColor(); 

原型方式代码示例

function proCar(){
}
proCar.prototype.name="原型";
proCar.prototype.color="blue";
proCar.prototype.price="10000";
proCar.prototype.getName=function(){
  document.write(this.name+"-----"+this.color+"<br>");
};
var car3=new proCar();
car3.getName();

原型方式缺陷示例

proCar.prototype.drivers = newArray("mike", "sue");
car3.drivers.push("matt");
alert(car3.drivers);//outputs "mike,sue,matt"
alert(car3.drivers);//outputs "mike,sue,matt"

动态原型方式代码示例

function autoProCar(name,color,price){
  this.name=name;
  this.color=color;
  this.price=price;
  this.drives=new Array("mike","sue");
  if(typeof autoProCar.initialized== "undefined"){
   autoProCar.prototype.getName =function(){
   document.write(this.name+"-----"+this.color+"<br>");
   };
   autoProCar.initialized=true;
  }
}
var car4=new autoProCar("动态原型","yellow","1234565");
car4.getName();
car4.drives.push("newOne");
document.write(car4.drives);