js面向对象之构造函数

最简单的面向对象程序
<script type="text/javascript"> ???var obj = new Object(); ???obj.qq = ‘1079161148‘; ???obj.name = ‘mr lan‘ ???obj.showName = function() { ???????alert(‘my name =‘ + this.name) ???} ???obj.showQQ = function() { ???????alert(‘my qq =‘ + this.qq) ???} ???obj.showName() ???obj.showQQ()</script>

封装重复使用的方法；
<script type="text/javascript"> ???function createPerson(name, qq) {//构造函数 构建出一个对象； ???????var obj = new Object(); ???????obj.qq = qq; ???????obj.name = name ???????obj.showName = function() { ???????????alert(‘my name =‘ + this.name) ???????} ???????obj.showQQ = function() { ???????????alert(‘my qq =‘ + this.qq) ???????} ???????//出厂 ???????return obj ???} ???var obj = createPerson(‘Mr Lan‘,‘1079161148‘); ???var obj2 = createPerson(‘Mr Li‘,‘1079161168‘); ???obj.showName(); ???obj.showQQ();</script>

//升级------->构造函数调用加new
<script type="text/javascript"> ???function createPerson(name, qq) { //构造函数 构建出一个对象； ???????this.qq = qq; ???????this.name = name ???????this.showName = function() { ???????????alert(‘my name =‘ + this.name) ???????} ???????this.showQQ = function() { ???????????alert(‘my qq =‘ + this.qq) ???????} ???} ???var obj = new createPerson(‘Mr Lan‘, ‘1079161148‘); ???var obj2 = new createPerson(‘Mr Li‘, ‘1079161168‘); ???obj.showName() ???obj.showQQ()

　　alert(obj.showName()==obj2.showName()) //false

</script>

//进阶面向对象编程
<script type="text/javascript"> ???//混合构造函数混合方式(构造函数配合原型) ???function createPerson(name, qq) { //构造函数加属性 ???????this.qq = qq; ???????this.name = name ???} ???createPerson.prototype.showName = function(){//原型加方法 ???????alert(‘my name =‘ + this.name) ???} ???createPerson.prototype.showQQ = function(){ ???????alert(‘my qq =‘ + this.qq) ???} ???var obj = new createPerson(‘Mr Lan‘, ‘1079161148‘); ???var obj2 = new createPerson(‘Mr Li‘, ‘1079161168‘); ???//obj.showName() //还可以继续用不影响使用 ???//obj.showQQ() ???alert(obj.showName()==obj2.showName())//true</script>