js去重复和取重复数据

js数组中取重复数据的方法：
方法一：去重复数据
<script>
Array.prototype.distinct=function(){
var a=[],b=[];
for(var prop in this){
var d = this[prop];
if (d===a[prop]) continue; //防止循环到prototype
if (b[d]!=1){
a.push(d);
b[d]=1;
}
}
return a;
}
var x=['a','b','c','d','b','a','e','a','b','c','d','b','a','e'];
document.write('原始数组:'+x);
document.write("<br />");
document.write('去重复后:'+x.distinct());
</script>
方法二：取重复数据
<script type="text/javascript">
Array.prototype.distinct=function(){
var a=[],b=[],c=[],d=[];
for(var prop in this){
var d = this[prop];
if (d===a[prop])
{
continue;
}//防止循环到prototype
if (b[d]!=1){
a.push(d);
b[d]=1;
}
else { c.push(d);
d[d]=1;
}
}
//return a;
return c.distinct1();
}
Array.prototype.distinct1=function(){
var a=[],b=[];
for(var prop in this){
var d = this[prop];
if (d===a[prop]) continue; //防止循环到prototype
if (b[d]!=1){
a.push(d);
b[d]=1;
}
}
return a;
}
var x=['a','b','c','d','b','a','e','a','b','c','d','b','a','e','f','f','g'];
document.write('原始数组:'+x);
document.write("<br />");
document.write('去重复后:'+x.distinct());
</script>