javascript面向对象程序设计高级特性经典教程(值得收藏)

var a = new Object();
a.x = 1, a.y = 2;

var b = { x : 1, y : 2 };

function Point(x, y){
 this.x = x;
 this.y = y;
}
var p = new Point(1,2);

//创建一个空对象
var hero = {};
//为hero对象增加属性和方法
hero.name = "JavaScript";
hero.value = "helloworld";
hero.sayName = function(){return "hello " + hero.name;};
//测试
alert(hero.name); //output javascript
alert(hero.sayName()); //output hello javascript
//删除hero对象的name属性
delete hero.name;
//测试
alert(hero.sayName()); //output hello undefined

//创建一个空对象
var hero = {};
//为hero对象增加属性和方法
hero.name = "javascript";
hero.value = "helloworld";
hero.sayName = function(){return "hello " + this.name;};
//测试
alert(hero.name); //output javascript
alert(hero.sayName()); //output hello javascript

var object = {};
var obj = new Object();

var object = {};
var obj = new Array();

//反转字符串示例
//定义一个字符串
var str = "a,b,c,d,e,f,g";
//利用String对象的split()方法，将字符串切割成一个数组
var arr = str.split(",");
//利用Array对象的reverse()方法，将数组中元素的顺序颠倒。
arr = arr.reverse();
//测试打印
alert(arr.toString());

var str = "hello";
var obj = new String("world");
alert(typeof str); //typeof string
alert(typeof obj); //typeof object

//判断字符串是否包含指定字符串示例
//定义两个要判断的字符串
var str = "abcdefg";
var substr = "efg";
/*
* 定义判断字符串是否包含指定字符串的函数
*  * 第一个参数：要判断的字符串
*  * 第二个参数：指定的字符串
*/
function sub(str,substr){
//将判断的字符串定义成String对象
var string = new String(str);
//截取判断的字符串
var result = string.substr(string.indexOf(substr),substr.length);
/*
* 判断截取后的字符串是否为空
*  * 为空，说明不包含指定字符串
*  * 不为空，说明包含指定字符串
*/
if(result==substr){
return true;
}else{
return false;
}
}
alert(sub(str,substr));

function Hero(name, color){
 this.name = name;
 this.color = color;
 this.whatareyou = function(){
 return "I am a " + this.color + " " + this.name;
 }
}
var hero = new Hero("javascript","red");
alert(hero.whatareyou()); //output I am a red javascript

Hero.prototype.price = 100;
Hero.prototype.rating = 3;
Hero.prototype.getInfo = function(){
 return "Rating: " + this.rating + " , Price: " + this.price;
}
alert(hero.getInfo()); //output Rating: 3 , Price: 100

Hero.prototype = {
 price : 100,
 rating : 3,
 getInfo : function(){
   return "Rating: " + this.rating + " , Price: " + this.price;
 }
};

function Hero(){
 this.name = "jscript";
}
Hero.prototype.name = "javascript";
var hero = new Hero();
alert(hero.name); //output jscript
delete hero.name;
alert(hero.name); //output javascript

//为原型 Array对象增加一个判断的函数
Array.prototype.inArray = function(color){
 for(var i = 0, len = this.length; i < len; i++){
 if(this[i] === color){
 return true;
 }
 }
 return false;
}
//定义一个Array对象
var a = ["red", "green", "blue"];
//测试
alert(a.inArray("red")); //true
alert(a.inArray("yellow")); //false

function A(){
this.name = "a";
this.toString = function(){return this.name};
}
function B(){
this.name = "b";
}
function C(){
this.name = "c";
this.age = 18;
this.getAge = function(){return this.age};
}
B.prototype = new A();
C.prototype = new B();

function A(){}
A.prototype.name = "a";
A.prototype.toString = function(){return this.name};
function B(){}
B.prototype = A.prototype;
B.prototype.name = "b";
function C(){}
C.prototype = B.prototype;
C.prototype.name = "c";
C.prototype.age = 18;
C.prototype.getAge = function(){return this.age};

//该函数接受一个对象并返回它的副本
function extendCopy(p){
 var z = {}; //定义一个空的对象z
 for(var i in p){ //var i =0 ; i < p.length ; i++
 z[i] = p[i]; //都当做数组处理的话，可以理解
 }
 //uber属性：将p作为z的父级，将z指向p的原型
 z.uber = p;
 return z;
}
//定义对象a，但是对象a不是函数对象 
var a = {
 name : "a",
 toStr : function(){return this.name;}
}
//定义对象b，但是对象b不是函数对象 
var b = extendCopy(a);
b.name = "b";
b.toStr = function(){return this.uber.toStr() + " , " + this.name;};
//定义对象c，但是对象c不是函数对象 
var c = extendCopy(b);
c.name = 18;
alert(c.toStr()); //output a , b , 18