js对象继承的实现的几种方式

<!-- javascript实现继承的几种方式-->

<script type="text/javascript">

/*

//javascript的继承

//1,对象冒出

function Parent(username)

{

this.username = username;

this.sayHello = function ()

{

alert(this.username);

}

}

function Child(username,password)

{

this.method = Parent;

this.method(username);

delete this.method;

this.password = password;

this.sayWord = function ()

{

alert(this.password);

}

}

var parent = new Parent("zhangsan");

var child = new Child("lisi","1234");

parent.sayHello();

child.sayHello();

child.sayWord();

// var obj= new Parent("zhangsan");

//obj.sayHello();

*/

/*

//javascript的继承

//2,Call方法方式 Funciton对象的方法

function test(str)

{

alert(this.name + "," + str)

}

object = new Object();

object.name = "aiguoliang";

//test.call(object,"zhangsan");

function Parent(username)

{

this.username = username;

this.sayHello = function ()

{

alert(this.username);

}

}

function Child(username,password)

{

Parent.call(this,username);

this.password = password;

this.sayWord = function ()

{

alert(this.password);

}

}

var parent = new Parent("zhangsan");

var child = new Child("list","123");

parent.sayHello();

child.sayWord();

child.sayHello();

*/

/*

//javascript的继承

//3,apply方法

function Parent(username,obj)

{

this.username = username;

this.obj = obj;

this.sayHello = function ()

{

alert(this.username + this.obj);

}

}

function Child(username,password)

{

var arr = new Array();

arr.push(username);

arr.push(password);

Parent.apply(this,arr);

this.password = password;

this.sayWord = function ()

{

alert(this.password);

}

}

var parent = new Parent("zhangsan","987");

var child = new Child("lisi","123");

parent.sayHello();

child.sayHello();

child.sayWord();

*/

/*

//javascript的继承

//4,原型链方式（prototype chain） 方式实现javaScript的继承

function Parent()

{

}

Parent.prototype.hello = "hello";

Parent.prototype.sayHello = function ()

{

alert(this.hello);

}

function Child()

{

}

Child.prototype= new Parent();

Child.prototype.word = 'word';

Child.prototype.sayWord = function ()

{

alert(this.word);

}

var child = new Child();

child.sayHello();

child.sayWord();

*/

/*

//javascript的继承

//5.使用混合的方式实现javascript的继承

function Parent(hello)

{

this.hello = hello;

}

Parent.prototype.sayHello = function ()

{

alert(this.hello);

}

function Child(hello,world)

{

Parent.call(this, hello);

this.world = world;

}

Child.prototype = new Parent();

Child.prototype.sayWorld = function ()

{

alert(this.world);

}

var child = new Child("zhangsan","123");

child.sayHello();

child.sayWorld()

*/

</script>