<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Insert title here</title></head><body><script type="text/javascript">/* * 初探 *///变量的定义var name = 'xxx';var email = 'xxx@163.com';var website = 'http://baidu.com';//对象的定义var X = {name:'xxx',email:'xxx@163.com',website:'http://baidu.com'}//成员方式显示//alert(X.website);//hash map方式显示//alert(X['website']);//函数var doSomething = function() {alert('Hello World');}//doSomething();var sayHello = function() {var hello = "Hello,I am "+this.name+", my email is: "+this.email+", my website is: "+this.website;alert(hello);}//直接赋值X.Hello = sayHello;//X.Hello();//规范写法//用function来做classvar Person = function(name, email, website) {this.name = name;this.email = email;this.website = website;this.sayHello = function() {var hello = "Hello, I am "+this.name +"my email is: "+this.email+"my website is: "+this.website;alert(hello);}}var X = new Person('xxx', 'xxx@163.com', 'http://baidu.com');//X.sayHello();//删除对象属性delete X.name;//或者delete X['name'];//X.sayHello();//alert(X.name);//属性配置 - Object.definePropertyvar X = Object.create(null);//设置一个属性 （属性名 ,属性配置信息）Object.definePropertyObject.defineProperty(X, "name", {value:"xxx", writable:true, configurable:true, enumerable:true});//设置多个属性（{属性名:属性配置信息, 属性名:属性配置信息}）Object.definePropertiesObject.defineProperties(X,{"email":{value:"xxx@163.com",writable:true,configurable:true,enumerable:true},"website":{value:"http://baidu.com",writable:true,configurable:true,enumerable:true}});//alert(X.email);/* * writable：这个属性的值是否可以改。 * configurable：这个属性的配置是否可以改。 * enumerable：这个属性是否能在for…in循环中遍历出来或在Object.keys中列举出来。 * value：属性值。 * get()/set(_value)：get和set访问器。 *///Get/Set访问器var age = 0;Object.defineProperty(X, "age", {get:function() {return age+1;},set:function(value) {age=value;}});X.age = 100;//调用set//alert(X.age)//调用getObject.defineProperty(X, "birth_year", {get:function() {var d = new Date();var y = d.getFullYear();return (y - this.age);},set:function(year) {var d = new Date();var y = d.getFullYear();this.age = y -year;}})//alert(X.birth_year);X.birth_year = 2000;//alert(X.age);var X = {name:"xxx",email:"xxx@163.com",website:"http://baidu.com",age:100,get birth_year() {var d = new Date();var y = d.getFullYear();return (y - this.age);},set birth_year(year) {var d = new Date();var y = d.getFullYear();this.age = y - year;}}//alert(X.birth_year);X.birth_year = 2000;//alert(X.age);//查看对象属性配置function listProperties(obj) {var newLine = '<br />';var names = Object.getOwnPropertyNames(obj);for(var i=0;i<names.length;i++) {var prop = names[i];document.write(prop+newLine);var descriptor = Object.getOwnPropertyDescriptor(obj,prop);for(var attr in descriptor){document.write("..."+attr+":"+descriptor[attr]);document.write(newLine);}}}//listProperties(X);//call, apply, bind和this//thisfunction print(text) {document.write(this.value+' - '+text+'<br/>');}var a = {value:10, print:print};var b = {value:20, print:print};//print('hello');//alert(a.print); ->print//a.print('a');//this a//b.print('b');//this b//a['print']等价于a.print//a['print']('a');//this a//call apply//print.call(a, 'a');//print.call(b, 'b');//print.apply(a, ['a']);//print.apply(b, ['b']);//bindvar p = print.bind(a);//p('a');//p.call(b, 'b');//p.apply(b, ['b']);//继承和重载var Person = Object.create(null);Object.defineProperties(Person,{"name":{value:"xxx"},"email":{value:"xxx@163.com"},"website":{value:"http://baidu.com"}});Person.sayHello = function() {var hello = "<p>Hello, I am "+this.name+",<br>"+"my email is: "+this.email+",<br>"+"my website is: "+this.website;document.write(hello+"<br>");}//Person.sayHello();var Student = Object.create(Person);Student.no = "1234567";Student.dept ="computer science";//使用Person的属性//document.write(Student.name+' '+Student.email+' '+Student.website+'<br>');//使用Person的方法//Student.sayHello();//重载sayHello方法Student.sayHello = function() {var hello = "<p>Hello, I am "+this.name+",<br>"+"my email is: "+this.email+",<br>"+"my websiteis: "+this.website+",<br>"+"my student no is: "+this.no+",<br>"+"my departent is: "+this.dept;document.write(hello+"<br>");}//Student.sayHello();//Prototype//Object.getPrototypeOf()//Student.name = 'aaa';//document.write('<p>'+Student.name+'</p>');//document.write('<p>'+Object.getPrototypeOf(Student).name+'</p>');Student.sayHello = function () {Object.getPrototypeOf(Student).sayHello.call(this);var hello = "my student no is:" +this.no+",<br>"+"my departent is:"+this.dept;document.write(hello+"<br>");}//Student.sayHello();//组合function Composition(target, source) {var desc = Object.getOwnPropertyDescriptor;var prop = Object.getOwnPropertyNames;var def_prop = Object.defineProperty;prop(source).forEach(function(key) {def_prop(target, key, desc(source, key));});return target;}//艺术家var Artist = Object.create(null);Artist.sing = function() {return this.name + ' starts singing...';}Artist.paint = function() {return this.name + ' starts painting...';}//运动员var Sporter = Object.create(null);Sporter.run = function() {return this.name + ' starts running...';}Sporter.swim = function() {return this.name + ' starts swimming...';}Composition(Person, Artist);//document.write(Person.sing() + '<br>');//document.write(Person.paint() + '<br>');//看看Person中有什么//document.write('<p>'+Object.keys(Person)+'<br>');//document.write(Person.name+'<br>');//Prototype和继承var plus = function(x,y) {document.write(x+'+'+y+'='+(x+y)+'<br>');return x+y;}var minus = function(x,y) {document.write(x+'-'+y+'='+(x-y)+'<br>');return x-y;}var operations = {'+':plus,'-':minus}var calculate = function(x, y, operation) {return operations[operation](x, y);}//calculate(12, 4, '+');//calculate(24, 3, '-');//prototype就是对一对象进行扩展var Cal = function(x, y) {this.x = x;this.y = y;}Cal.prototype.operations = {'+':function(x,y) {return x+y},'-':function(x,y) {return x-y}}Cal.prototype.calculate = function(operation) {return this.operations[operation](this.x,this.y);}var c = new Cal(4,5);//alert(c.calculate('+'));//alert(c.calculate('-'));//继承var Person = function(name, email, website) {this.name = name;this.email = email;this.website = website;}Person.prototype.sayHello = function() {var hello = "Hello, I am "+this.name+",<br>"+"my email is: "+this.email+",<br>"+"my website is: "+this.website;return hello;}var Student = function(name,email,website,no,dept) {var proto = Object.getPrototypeOf;//Student.prototype = Object.create(Person.prototype);//call()赋值、获取proto(Student.prototype).constructor.call(this,name,email,website);this.no = no;this.dept = dept;}//继承prototypeStudent.prototype = Object.create(Person.prototype);//重置构造函数//Student.prototype.constructor = Student;//重载sayHello()Student.prototype.sayHello = function() {var proto = Object.getPrototypeOf;var hello = proto(Student.prototype).sayHello.call(this)+'<br>';hello += "my student no is: "+this.no+",<br>"+"my departent is: "+this.dept;return hello;}var me = new Student("motian06","motian06@126.com","http://baidu.com","88888888","jinrong");document.write(me.sayHello());</script></body></html>
