c#比较两个IP地址大小

/**//// <summary>
        /// 确保结束ip大于开始ip
        /// </summary>
        private bool validateIP(string startIP,string endIP)
        ...{
            // 分离出ip中的四个数字位
            string[] startIPArray = startIP.Split('.');
            string[] endIPArray = endIP.Split('.');

            // 取得各个数字
            long[] startIPNum = new long[4];
            long[] endIPNum = new long[4];
            for (int i = 0; i < 4; i++)
            ...{
                startIPNum[i] = long.Parse(startIPArray[i].Trim());
                endIPNum[i] = long.Parse(endIPArray[i].Trim());
            }

            // 各个数字乘以相应的数量级
            long startIPNumTotal = startIPNum[0] * 256 * 256 * 256 + startIPNum[1] * 256 * 256 + startIPNum[2] * 256 + startIPNum[3];
            long endIPNumTotal = endIPNum[0] * 256 * 256 * 256 + endIPNum[1] * 256 * 256 + endIPNum[2] * 256 + endIPNum[3];

            if (startIPNumTotal > endIPNumTotal)
            ...{
                return false;
            }
            else
            ...{
                return true;
            }
        }