生成不重复long型数字

public long GetCode(string shardField)
        {
            uint code = 0;
            shardField = shardField.Trim();
            for (int i = 0; i < shardField.Length; i += 2)
            {
                code *= 16777619;
                code ^= shardField[i];
            }
            var ss = code;

            return ss;
        }