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Javascript创建对象的几种方式

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//1、工厂模式
 
                function createCar(){
 
                                var car = new Object();
 
                                car.color="red";
 
                                car.doors=4;
 
                                car.mpg=23;
 
                                car.showColor=function(){
 
                                                alert(this.color);
 
                                }
 
                                return car
 
                }
 
                
 
                /*
 
                由于上述创建的对象的属性都一样,所以可以通过参数化实现不一样
 
                */
 
                function createCar(sColor,iDoor,iMpg){
 
                                var car = new Object();
 
                                car.color=sColor;
 
                                car.doors=iDoor;
 
                                car.mpg=iMpg;
 
                                car.showColor=function(){
 
                                                alert(this.color);
 
                                }
 
                                return car
 
                }
 
                //以上这种方式创的每一个对象都创建了showColor方法,所以造成重复
 
                function showColor(){
 
                                alert(this.color);
 
                }
 
                function createCar(sColor,iDoor,iMpg){
 
                                var car = new Object();
 
                                car.color=sColor;
 
                                car.doors=iDoor;
 
                                car.mpg=iMpg;
 
                                car.showColor=showColor;
 
                                return car
 
                }
 
//2、构造函数方式
 
                function createCar(sColor,iDoor,iMpg){
 
                                this.color = sColor;
 
                                this.iDoor = iDoor;
 
                                this.iMpg = iMpg;
 
                                this.showColor=function(){
 
                                                alert(this.color)
 
                                }
 
                }
 
//3、原型模式
 
                function car(){}
 
                
 
                car.prototype.color="red";
 
                car.prototype.Door=4;
 
                car.prototype.mpg=23;
 
                car.prototype.showColor=function(){
 
                                alert(this.color);
 
                }
 
                //但是这种模式有一个特点就是创建出来的每一个对象的属性都一样
 
//4、构造函数/原型混合模式
 
                function car(iColor,sDoor,iMpg){
 
                                this.color=iColor;
 
                                this.doors=sDoor;
 
                                this.mpg=iMpg;
 
                }
 
                car.prototype.showColor=function(){
 
                                alert(this.color);
 
                }
 
//5、动态原型模式
 
                function car(icolor,sdoor,impg){
 
                                this.color=icolor;
 
                                this.sdoor=door;
 
                                this.impg=mpg;
 
                                if(typeof car._initialized=="undefined"){
 
                                                car.prototype.showColor=function(){
 
                                                                alert(this.color)
 
                                                }
 
                                }
 
                                car._initialized=true;
 
                }
 
                
 
//6、混合模式
 
//混合模式的定义方法跟工厂模式很像,但是实例化是却不同,工厂模式不需要new,但是混合模式需要new操作符
 
  
 
//继承的几种方式
 
//1、对象冒充
 
                function ClassA(sColor){
 
                                this.color=sColor;
 
                                this.sayColor=function(){
 
                                                alert(this.color);
 
                                }
 
                }
 
                //所有的新的属性和方法必须在删除方法后
 
                function ClassB(sColor,sName){
 
                                this.newMethod=ClassA;
 
                                this.newMethod=(sColor);
 
                                delete this.newMethod;
 
                                
 
                                this.name=sName;
 
                                this.sayName = function(){
 
                                                alert(sName);
 
                                }
 
                }
 
//2、call方法
 
                function ClassB(sColor,sName){
 
                                ClassA.call(this,sColor);
 
                                
 
                                this.name=sName;
 
                                this.sayName=function(){
 
                                                alert(sName);
 
                                }
 
                }
 
//3、apply方法
 
                function ClassB(sColor,sName){
 
                                ClassA.apply(this,new Array(sColor))
 
                                
 
                                this.sName=sName;
 
                                this.sayName=function(){
 
                                                alert(this.name);
 
                                }
 
                }
 
                
 
                //或者用arguments
 
                function ClassB(sColor,sName){
 
                                ClassA.apply(this,arguments)
 
                                
 
                                this.sName=sName;
 
                                this.sayName=function(){
 
                                                alert(this.name);
 
                                }
 
                }
 
                
 
//4、原型链
 
                function ClassA(){}
 
                ClassA.prototype.color="red";
 
                ClassA.prototype.sayColor=function(){
 
                                alert(color);
 
                }
 
                
 
                function ClassB(){}
 
                ClassB.prototype= new ClassA();
 
                ClassB.prototype.name="";
 
                ClassB.prototype.sayName = function(){
 
                                alert(this.name);
 
                }
 
                
 
//5、混合方式
 
                function ClassA(sColor){
 
                                this.color=sColor;
 
                }
 
                ClassA.prototype.showColor=function(){
 
                                alert(this.color);
 
                }
 
                
 
                function ClassB(sColor,sName){
 
                                ClassA.call(this,sColor);
 
                                this.name=sName;
 
                }
 
                
 
                ClassB.prototype=new ClassA();
 
                ClassB.prototype.sayName=function(){
 
                                alert(this.name)
 
                }