原文地址：http://www.cnblogs.com/yupeng/p/3478069.html
1.Object.create() 是什么？
Object.create(proto [, propertiesObject ]) 是E5中提出的一种新的对象创建方式，第一个参数是要继承的原型，如果不是一个子函数，可以传一个null，第二个参数是对象的属性描述符，这个参数是可选的。
例如：
1 function Car (desc) {
2 this.desc = desc;
3 this.color = "red";
4 }
5
6 Car.prototype = {
7 getInfo: function() {
8 return ‘A ‘ + this.color + ‘ ‘ + this.desc + ‘.‘;
9 }
10 };
11 //instantiate object using the constructor function
12 var car = Object.create(Car.prototype);
13 car.color = "blue";
14 alert(car.getInfo());
结果为:A blue undefined.
2.propertiesObject 参数的详细解释：（默认都为false）
数据属性
- writable:是否可任意写
- configurable：是否能够删除，是否能够被修改
- enumerable：是否能用 for in 枚举
- value：值
访问属性：
- get(): 访问
- set(): 设置
3.例子：直接看例子就知道怎么用。
1 <!DOCTYPE html>
2 <html>
3 <head>
4 <title>yupeng‘s document </title>
5 <meta charset="utf-8"/>
6 </head>
7 <body>
8 <script type="text/javascript">
9
10 var obj = {
11
12 a:function(){
13 console.log(100)
14 },
15 b:function(){
16 console.log(200)
17 },
18 c:function(){
19 console.log(300)
20 }
21
22 }
23
24 var newObj = {};
25
26 newObj = Object.create(obj,{
27 t1:{
28 value:‘yupeng‘,
29 writable:true
30 },
31 bar: {
32 configurable: false,
33 get: function() { return bar; },
34 set: function(value) { bar=value }
35 }
36
37 })
38
39 console.log(newObj.a());
40 console.log(newObj.t1);
41 newObj.t1=‘yupeng1‘
42 console.log(newObj.t1);
43 newObj.bar=201;
44 console.log(newObj.bar)
45
46 function Parent() { }
47 var parent = new Parent();
48 var child = Object.create(parent, {
49 dataDescriptor: {
50 value: "This property uses this string as its value.",
51 writable: true,
52 enumerable: true
53 },
54 accessorDescriptor: {
55 get: function () { return "I am returning: " + accessorDescriptor; },
56 set: function (val) { accessorDescriptor = val; },
57 configurable: true
58 }
59 });
60
61 child.accessorDescriptor = ‘YUPENG‘;
62 console.log(child.accessorDescriptor);
63
64
65
66 var Car2 = function(){
67 this.name = ‘aaaaaa‘
68 } //this is an empty object, like {}
69 Car2.prototype = {
70 getInfo: function() {
71 return ‘A ‘ + this.color + ‘ ‘ + this.desc + ‘.‘;
72 }
73 };
74
75 var newCar = new Car2();
76
77 var car2 = Object.create(newCar, {
78 //value properties
79 color: { writable: true, configurable:true, value: ‘red‘ },
80 //concrete desc value
81 rawDesc: { writable: true, configurable:true, value: ‘Porsche boxter‘ },
82 // data properties (assigned using getters and setters)
83 desc: {
84 configurable:true,
85 get: function () { return this.rawDesc.toUpperCase(); },
86 set: function (value) { this.rawDesc = value.toLowerCase(); }
87 }
88 });
89 car2.color = ‘blue‘;
90 console.log(car2.getInfo());
91 car2.desc = "XXXXXXXX";
92 console.log(car2.getInfo());
93 console.log(car2.name);
94
95
96
97 </script>
98 </body>
99 </html>
结果为：
100
yupeng
yupeng1
201
I am returning: YUPENG
A blue PORSCHE BOXTER.
A blue XXXXXXXX.
aaaaaa
时间： 2024-12-28 00:54:16