<html>
<head>
</head>
<body>
<script type="text/javascript">
//繼承之對象冒充方式,可以繼承多個父類
function user(name){
this.name = name;
this.sayname = function(){
alert(this.name);
}
}
function student(name,score){
//user(name);
this.temp = user;
this.temp(name);
delete this.temp;
this.score = score;
this.sayscore = function(){
alert(this.score);
}
}
var s = new student('tom',33);
//s.sayname();
//s.sayscore();
//用call（）函數實現繼承
function user(name){
this.name = name;
this.sayname = function(){
alert(this.name);
}
}
function student(name,score){
user.call(this,name);
this.score = score;
this.sayscore = function(){
alert(this.score);
}
}
var s = new student('tom',33);
//s.sayname();
//s.sayscore();
//用apply（）函數實現繼承
function user(name){
this.name = name;
this.sayname = function(){
alert(this.name);
}
}
function student(name,score){
user.apply(this,[name]);
this.score = score;
this.sayscore = function(){
alert(this.score);
}
}
var s = new student('tom',33);
//s.sayname();
//s.sayscore();
//原型鏈方式實現繼承
//1.將父類中所用通過prototype設置的屬性或方法放到子類中
//2.并覆蓋子類中所以的prototype的設置
//3.所以子類自己的所以的prototype的設置要放在繼承父類的下面
//4.缺點是不支持多個繼承，構造函數不能有參數
function user(){}
user.prototype.name = '';
user.prototype.say = function(){
alert(this.name);
}
function student(){}
student.prototype =new user();
student.prototype.age = 0;
student.prototype.show = function(){
alert(this.age);
}
var s = new student();
s.name = 'tom';
s.age = 44;
//s.say();
//s.show();
//alert(s instanceof user);
//alert(s instanceof student);
//混合模式實現繼承
function user(name){
this.name = name;
}
user.prototype.sayname = function(){
alert(this.name);
}
function student(name){
user.call(this.name);
}
//將user中所有通過prototype設置的方法放到student中
student.prototype = new user();
student.prototype.age = 0;
student.prototype.sayage = function(){
alert(this.age);
}
var s = new student();
s.name = 'tom';
s.age = 44;
s.sayname();
s.sayage();
alert(s instanceof user);
alert(s instanceof student);
</script>
</body>
<html/>