数组去重记录下

Array.prototype.distinct=function(){
            var ret=[];
            for(i=0,ii=this.length;i<1*ii;i++)
            {
                for(j=i+1;j<1*this.length;)
                {
                    if(this[i]===this[j])
                    {
                        ret.push(this.splice(j,1)[0]);
                    }else{
                            j++;
                         }
                }
            }
            this.ret=ret;
            return this;
        }
//测试
alert(['a','b','c','c','d','b','a','a','b','d'].distinct());
//alert(['a','b','c','c','d','b','a','a','b','d'].distinct().ret);

2

Array.prototype.makeUnique=function()
{
    var a = [],
        b = {},
        ret = [];
    for (var i=0,l=this.length;i < 1*l;i++)
    {
        if(!(this[i] in b))
        {
             a.push(this[i]);
             b[this[i]]=this[i];
        }
        else
        {
          ret.push(this[i]);
        }
    }
    a.ret = ret;
    return a;
}
//测试
alert(['a','b','c','c','d','b','a','a','b','d'].makeUnique());
alert(['a','b','c','c','d','b','a','a','b','d'].makeUnique().ret);

3

function unique(oArray) {
  var a = {}, b = [];
  oArray instanceof Array ? function(o) {
    for(var i = 0;i < o.length;i++) {
      a[o[i]] = o[i]
    }
    for(var i in a) {
      b.push(a[i])
    }
  }(oArray) : b.push("\u4f60\u4e2b\u4f20\u7684\u662f\u4ec0\u4e48\u73a9\u610f\uff1f");
  return b
};