js数组去重复

Array.prototype.unique4 = function()
{
	this.sort();
	var re=[this[0]];
	for(var i = 1; i < this.length; i++)
	{
		if( this[i] !== re[re.length-1])
		{
			re.push(this[i]);
		}
	}
	return re;
}