JavaScript高级<3>

JavaScript 自定义对象

创建对象方式：方式一，对象初始化器方式；

方式二，构造函数方式；

<script type="text/javascript">
var cc = {
name : "cc",
age : 22,
shout : function() {
alert("我是：" + this.name + "今年" + this.age + "岁了！");
},
action : function() {
alert("会吃");
}
};

alert(cc.name);
alert(cc.age);
cc.shout();
cc.action();

function Dog(name, age) {
this.name = name;
this.age = age;
this.shout = function() {
alert("我是：" + this.name + "今年" + this.age + "岁了！");
};
this.action = function() {
alert("eat");
};
}

var jack = new Dog("jack", 1);
alert(jack.name);
alert(jack.age);
jack.shout();
jack.action();
</script>

对象属性定义：私有属性；对象属性；类属性

<script type="text/javascript">
function C(){
this.Object="对象属性";
C.prototype.Object2="对象属性2";
var privatePro="私有属性";
}
C.classPro="类属性";

alert(C.classPro);
var c=new C();
alert(c.Object);
alert(c.Object2);
</script>

对象方法定义：私有方法；对象方法；类方法；

<script type="text/javascript">
function C() {
var privateFunc = function() {
alert("私有方法");
};
privateFunc();
this.objFunc = function() {
alert("对象方法");
};
C.prototype.objFunc2 = function() {
alert("对象方法2");
};
}
C.classFunc = function() {
alert("类方法");
};
C.classFunc();
var c = new C();
c.objFunc();
c.objFunc2();
</script>

JavaScript 实现封装性；上面例子便是。

JavaScript实现继承性；

Apply()实现属性和方法的继承；

Prototype实现原型的继承；

<script type="text/javascript">
function Animal(name,age){
this.name=name;
this.age=age;
this.shout=function(){
alert("大家好!");
};
}

function Dog(name,age){
Animal.apply(this, [name,age]);
}

var jack=new Dog("jack",1);
alert(jack.name);
alert(jack.age);
jack.shout();
</script>

Dog.prototype=new Animal();

JavaScript实现多态特征；

<script type="text/javascript">
function Animal() {
this.shout = function() {
alert("动物!");
};
}

function Dog() {
this.shout = function() {
alert("狗");
};
}
Dog.prototype = new Animal();
function Cat() {
this.shout = function() {
alert("猫");
};
}
Cat.prototype = new Animal();

function shout(animal){
if(animal instanceof Animal){
animal.shout();
}
}

var dog=new Dog();
var cat=new Cat();
shout(dog);
shout(cat);
</script>