数字字符串检查

#region 数字字符串检查
        /// <summary>
        /// 检查Request查询字符串的键值，是否是数字，最大长度限制
        /// </summary>
        /// <param name="req">Request</param>
        /// <param name="inputKey">Request的键值</param>
        /// <param name="maxLen">最大长度</param>
        /// <returns>返回Request查询字符串</returns>
        public static string FetchInputDigit(HttpRequest req, string inputKey, int maxLen)
        {
            string retVal = string.Empty;

            if (inputKey != null && inputKey != string.Empty)
            {
                retVal = req.QueryString[inputKey];
                if (null == retVal)
                    retVal = req.Form[inputKey];
                if (null != retVal)
                {
                    retVal = SqlText(retVal, maxLen);
                    if (!IsNumber(retVal))
                        retVal = string.Empty;
                }
            }
            if (retVal == null)
                retVal = string.Empty;
            return retVal;
        }

        /// <summary>
        /// 是否数字字符串
        /// </summary>
        /// <param name="inputData">输入字符串</param>
        /// <returns></returns>
        public static bool IsNumber(string inputData)
        {
            Match m = RegNumber.Match(inputData);
            return m.Success;
        }

        /// <summary>
        /// 是否数字字符串可带正负号
        /// </summary>
        /// <param name="inputData">输入字符串</param>
        /// <returns></returns>
        public static bool IsNumberSign(string inputData)
        {
            Match m = RegNumberSign.Match(inputData);
            return m.Success;
        }

        /// <summary>
        /// 是否是浮点数
        /// </summary>
        /// <param name="inputData">输入字符串</param>
        /// <returns></returns>
        public static bool IsDecimal(string inputData)
        {
            Match m = RegDecimal.Match(inputData);
            return m.Success;
        }

        /// <summary>
        /// 是否是浮点数可带正负号
        /// </summary>
        /// <param name="inputData">输入字符串</param>
        /// <returns></returns>
        public static bool IsDecimalSign(string inputData)
        {
            Match m = RegDecimalSign.Match(inputData);
            return m.Success;
        }
        #endregion