js实现数组去掉重复的数据

<SCRIPT LANGUAGE="JavaScript">
Array.prototype.deleteEle=function(){
    var arr=this,o={},newArr=[],i,n;
    for( i=0;i<arr.length;i++){
        n=arr[i]+typeof(arr[i]);//如果不需要类型判断，直接将后面的去掉即可
        if(typeof(o[n])==="undefined"){
            newArr[newArr.length]=arr[i]
            o[n]=1;//缓存
        }
    }
    return newArr;
}
var x= [1,2,3,4,5,2,3,4,6,7,8];
document.write('原始数组:'+x);
document.write("<br />");
document.write('去重复后:'+x.deleteEle());
 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>