JS给字符串排序

function quick_sort(arr)
            {
                var arry1, arry2, mid;

                if (arr.length < 2) return arr;
                else if (arr.length == 2)
                    if (arr[0] > arr[1])
                        return arr.reverse();
                    else
                        return arr;
                else
                {
                    arry1 = new Array();
                    arry2 = new Array();
                    mid = arr[0];
                    for (var i = 1; i < arr.length; i++)
                    {
                        if (arr[i] < mid)
                            arry1.push(arr[i]);
                        else 
                            arry2.push(arr[i]);
                    }
                }
                return (quick_sort(arry1).concat(mid, quick_sort(arry2)));
            }