SOURCE

Array.prototype.uniqueFuc1=function(){
    var temp=[];
    var res=[];
    var flag;
    for(var i=0;i<this.length;i++){
        var flag=true;
        for(var j=i+1;j<this.length;j++){
            if(this[j]==this[i]){
                flag=false;
                break;
            }    
        }   
        if(flag){
				  res[res.length]=this[i];	
          //  res.push(this[i]);
          }
    }
    return res;
};
Array.prototype.uniqueFuc2=function(){
	var res=[];
	var tempJson={};
	for(var i=0;i<this.length;i++){
		if(!tempJson[this[i]]){
			res.push(this[i]);
			tempJson[this[i]]="sth";
		}
	}
	return res;
}
Array.prototype.uniqueFuc3=function(){
	var res=[this[0]];
	var flag;
	for(var i=1;i<this.length;i++){
		var flag=true;
		for(var j=0;j<res.length;j++){
			if(res[j]==this[i]){
				flag=false;
				break;
			}
		}
		if(flag){
			res.push(this[i]);
		}
	}
	return res;
}
var test=[1,1,2,3,4,5,6,78,9,123,22,2,4,6,6,6,7,0,11,123,222,23,222];
var result1=test.uniqueFuc1();
document.getElementById('result1').innerHTML=result1.toString();
var result2=test.uniqueFuc2();
document.getElementById('result2').innerHTML=result2.toString();
var result3=test.uniqueFuc3();
document.getElementById('result3').innerHTML=result3.toString();

<div id="result1">等待数据</div>
<div id="result2">等待数据</div>
<div id="result3">等待数据</div>