真是百看不如一練啊
/*var box= new Object(); //創(chuàng)建一個(gè)對(duì)象
box.name= "xiaoju";? //給對(duì)象添加一個(gè)屬性
box.age = 100;
box.run = function(){? //定義一個(gè)方法
return this.name + this.age + "運(yùn)行中...";
}
var box1 = new Object();
box1.name = "nanlan";
box1.age = 200;
box1.run = function(){
return this.name +this.age;
}*/
/*alert(box.run());*/
//object構(gòu)造函數(shù)創(chuàng)建多個(gè)對(duì)象，容易造成代碼冗余
var box= new Object(); //創(chuàng)建一個(gè)對(duì)象
box.name= "xiaoju";? //給對(duì)象添加一個(gè)屬性
box.age = 100;
box.run = function(){? //定義一個(gè)方法
return this.name + this.age + "運(yùn)行中...";
}
var box1 = box;
box1.name = "nanlan";
box1.age = 200;
box1.run = function(){
return this.name +this.age;
}
alert(box.run());
alert(boxbdnare 1.run());
*/
//工廠(chǎng)模式，用函數(shù)封裝特定接口創(chuàng)建對(duì)象的細(xì)節(jié)。工廠(chǎng)模式雖然解決了多個(gè)對(duì)象相似的問(wèn)題，但是并沒(méi)有解決對(duì)象識(shí)別的問(wèn)題
function createObject(name,age){
varobj =newObject();
obj.name = name;
obj.age = age;
obj.run =function(){
return this.name +this.age +"運(yùn)行中";
};//方法必須加上分號(hào)
returnobj;//返回對(duì)象引用，在工廠(chǎng)模式當(dāng)中，必須有返回語(yǔ)句
}//函數(shù)可以不用
function createObject2(name,age){
varobj =newObject();
obj.name = name;
obj.age = age;
obj.run =function(){
return this.name +this.age +"運(yùn)行中";
};//方法必須加上分號(hào)
return obj;//返回對(duì)象引用，在工廠(chǎng)模式當(dāng)中，必須有返回語(yǔ)句
} //函數(shù)可以不用加分號(hào)
varbox =? createObject("nanlan",20);
varbox1 =? createObject("xiaoju",21);
varbox2 = createObject("yunju",22);
/*
alert(box.run());
alert(box1.run());*/
alert(boxinstanceofObject);
alert(box1instanceofObject);
alert(box2instanceofObject);
//這三個(gè)提示框都是ture，可是怎么它們是誰(shuí)的對(duì)象呢，box 、box1是createObject的對(duì)象，box2是createObject2的對(duì)象，所以有了以下的方式——構(gòu)造函數(shù)模式
//構(gòu)造函數(shù)模式,解決了Object多個(gè)實(shí)例的問(wèn)題和工廠(chǎng)模式對(duì)象識(shí)別的問(wèn)題
function? Box(user,age){
this.user = user;
this.age = age;
this.run = run;
}
function? Desk(user,age){
this.user = user;
this.age = age;
this.run = function（）{
return this.name + this.age;
}
}
function run(){ ? //把構(gòu)造內(nèi)部的方法通過(guò)全局實(shí)現(xiàn)
return this.user + this.age;
}
//構(gòu)造函數(shù)沒(méi)有new Object() ,但它后臺(tái)自動(dòng) var obj = new Object;
//必須使用new構(gòu)造函數(shù)名，new Box(),Box第一個(gè)字母也是大寫(xiě)的
//必須使用new 運(yùn)算符
var box1 = new Box("nanlan",20);
var box2 = new Box("xiaoju",21);
alert( box1 instanceof? Object);?
alert( typeof box2);
alert(box1 instanceof? Box);
alert(box2 instanceof? Box);
alert(box3 instanceof? Box); //構(gòu)造函數(shù)能夠彌補(bǔ)工廠(chǎng)模式的缺點(diǎn)，即對(duì)象識(shí)別的問(wèn)題，這句代碼已經(jīng)得到體現(xiàn)，這三個(gè)提示框的輸出結(jié)果是ture，ture，false
var o = {};? //對(duì)象冒充
Box.call(o,"juju",20);
alert(o.run());*/
alert(box1.run() == box2.run()); //結(jié)果是false，因?yàn)樗麄儽容^的是地址
原型模式
function Box(){}
Box.prototype = {
constructor:Box,
name:'Lee',
age:100,
family:['哥哥','姐姐','妹妹'],
run: function(){
return this.name + this.age +"運(yùn)行中"
}
};
var box1 = new Box();
/!*alert(box1.family);*!/
//box1.family=["蘋(píng)果","香蕉","梨子"];
box1.family.push("蘋(píng)果","香蕉","梨子");
box1.name="xiaoju";
alert(box1.family);
var box2 = new Box();
//alert( box2.family); //結(jié)果是 哥哥、姐姐、妹妹
alert(box2.family); // 結(jié)果是哥哥、姐姐、妹妹,蘋(píng)果,香蕉,梨子
*/
//我的天那，這是原型模式的一個(gè)缺點(diǎn)。按道理來(lái)說(shuō)實(shí)例是不能修改原型當(dāng)中的實(shí)例屬性和方法的，但是
//很明顯在這里被修改了。原因是原型中所有屬性是很多實(shí)例共享的，共享對(duì)于函數(shù)非常合適，對(duì)于包含基本類(lèi)型的
//也還可以，但是如果屬性包含引用類(lèi)型，就存在一定的問(wèn)題。解決辦法是通過(guò)組合構(gòu)造函數(shù)+原型模式去寫(xiě)
/*/組合構(gòu)造函數(shù) + 原型模式*/
function Box(name,age){? //保持獨(dú)立的用構(gòu)造函數(shù)
this.name = name;
this.age = age;
this.family = ["哥哥","姐姐","妹妹"];
}
Box.prototype = {? //保持共享的用原型
constructor: Box,
run:function(){
return this.name + this.age;
}
}
var box1 = new Box('nanlan',20);
box1.family.push('弟弟');
alert(box1.family);
var box2 = new Box("xiaoju",21);
alert(box2.family); //結(jié)果是哥哥、姐姐、妹妹
/*//寄生構(gòu)造函數(shù) = 工廠(chǎng)模式+構(gòu)造函數(shù)模式
function Box(name,age){
var obj = new Object();
obj.name = name;
obj.age = age;
obj.run = function(){
return this.name + this.age;
}
return obj;
}
var box1 = new Box('Lee',100);
alert(box1.run());
var box2 = new Box('Jack',200);
alert(box2.run());*/
//穩(wěn)妥構(gòu)造函數(shù)
function Box(name,age){
var obj =new Object();
obj.name = name;
obj.age = age;
obj.run = function(){
return this.name +this.age;
}
return obj;
}
varbox1 = Box('nanlan',200);
alert(box1.run());
varbox2 = Box('xiaoju',100);
alert(box2.run());
