中比较两个对象是否相等，给Object对象开展了一个实现而已，象java一样可以只给自己想要的类重写equals方法。
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01 Object.prototype.equals = function(obj){
02 if(this == obj)
03 return true;
04 if(typeof(obj)=="undefined"||obj==null||typeof(obj)!="object")
05 return false;
06 var length = 0; var length1=0;
07 for(var ele in this) {
08 length++;
09 }
10 for(var ele in obj) {
11 length1++;
12 }
13 if(length!=length1)
14 return false;
15 if(obj.constructor==this.constructor){
16 for(var ele in this){
17 if(typeof(this[ele])=="object") {
18 if(!this[ele].equals(obj[ele]))
19 return false;
20 }
21 else if(typeof(this[ele])=="function"){
22 if(!this[ele].toString().equals(obj[ele].toString()))
23 return false;
24 }
25 else if(this[ele]!=obj[ele])
26 return false;
27 }
28 return true;
29 }
30 return false;
31 };
示例如下：
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1 var p1 = {name:"jack",age:18};
2 var p2 = {name:"lucy",age:10};
3 var p3 = {name:"jack",age:18};
4
5
6 console.log(p1.equals(p2));//false
7 console.log(p1.equals(p3));//true
8 console.log(p1.equals({name:"jack",age:18}));//true
