C#常用公共方法

 public static class CommonHelper
    {
        /// <summary>
        /// 是否是手机请求
        /// </summary>
        /// <param name="context"></param>
        /// <returns></returns>
        public static bool IsAppRequst(HttpContextBase context)
        {
            try
            {
                HttpRequestBase Request = context.Request;
                string str_u = Request.ServerVariables["HTTP_USER_AGENT"];
                Regex b = new Regex(@"android.+mobile|avantgo|bada/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|iris|kindle|lge |maemo|midp|mmp|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)/|plucker|pocket|psp|symbian|treo|up.(browser|link)|vodafone|wap|windows (ce|phone)|xda|xiino", RegexOptions.IgnoreCase | RegexOptions.Multiline);
                Regex v = new Regex(@"1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw-(n|u)|c55/|capi|ccwa|cdm-|cell|chtm|cldc|cmd-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc-s|devi|dica|dmob|do(c|p)o|ds(12|-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(-|_)|g1 u|g560|gene|gf-5|g-mo|go(.w|od)|gr(ad|un)|haie|hcit|hd-(m|p|t)|hei-|hi(pt|ta)|hp( i|ip)|hs-c|ht(c(-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i-(20|go|ma)|i230|iac( |-|/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |/)|klon|kpt |kwc-|kyo(c|k)|le(no|xi)|lg( g|/(k|l|u)|50|54|-[a-w])|libw|lynx|m1-w|m3ga|m50/|ma(te|ui|xo)|mc(01|21|ca)|m-cr|me(di|rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|-([1-8]|c))|phil|pire|pl(ay|uc)|pn-2|po(ck|rt|se)|prox|psio|pt-g|qa-a|qc(07|12|21|32|60|-[2-7]|i-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55/|sa(ge|ma|mm|ms|ny|va)|sc(01|h-|oo|p-)|sdk/|se(c(-|0|1)|47|mc|nd|ri)|sgh-|shar|sie(-|m)|sk-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h-|v-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl-|tdg-|tel(i|m)|tim-|t-mo|to(pl|sh)|ts(70|m-|m3|m5)|tx-9|up(.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|yas-|your|zeto|zte-", RegexOptions.IgnoreCase | RegexOptions.Multiline);
                if (!(b.IsMatch(str_u) || v.IsMatch(str_u.Substring(0, 4))))
                {
                    return false;
                }
                else
                {
                    return true;
                }
            }
            catch (Exception)
            {
                return false;
            }
        }

        private static char[] constant ={
                            '0','1','2','3','4','5','6','7','8','9',
                            'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z',
                            'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'
        };
        /// <summary>
        /// 生成指定随机数
        /// </summary>
        /// <param name="Length"></param>
        /// <returns></returns>
        public static string GenerateRandom(int Length)
        {
            System.Text.StringBuilder newRandom = new System.Text.StringBuilder(62);
            Random rd = new Random();
            for (int i = 0; i < Length; i++)
            {
                newRandom.Append(constant[rd.Next(62)]);
            }
            return newRandom.ToString();
        }
        /// <summary>
        /// 将字json字符串转换为对象集合
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="JsonStr"></param>
        /// <returns></returns>
        public static List<T> ScriptSerialize<T>(this string JsonStr)
        {
            if (!string.IsNullOrEmpty(JsonStr))
            {
                JavaScriptSerializer Serializer = new JavaScriptSerializer();
                Serializer.MaxJsonLength = Int32.MaxValue;
                List<T> objs = Serializer.Deserialize<List<T>>(JsonStr);
                return objs;
            }
            else
            {
                return null;
            }
        }
        /// <summary>
        /// 将对象转换为json
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="t"></param>
        /// <returns></returns>
        public static string ScriptSerialize<T>(T t)
        {
            JavaScriptSerializer js = new JavaScriptSerializer();
            return js.Serialize(t);
        }
        public static void ToPagingProcess<T>(this IEnumerable<T> item, int pageSize, Action<IEnumerable<T>> singlePageList) where T : class
        {
            if (item != null && item.Count() > 0)
            {
                var cnt = item.Count();
                var totalPages = item.Count() / pageSize;
                if (cnt % pageSize > 0) totalPages += 1;

                for (int pageIndex = 1; pageIndex <= totalPages; pageIndex++)
                {
                    var currentPageItems = item.Skip((pageIndex - 1) * pageSize).Take(pageSize);
                    singlePageList(currentPageItems);
                }
            }
        }

        #region 时间
        /// <summary>
        /// 最大时间
        /// </summary>
        /// <param name="dateTime"></param>
        /// <returns></returns>
        public static DateTime? GetMaxDateTime(DateTime? dateTime)
        {
            if (dateTime.HasValue)
            {
                return dateTime.Value.Date.AddDays(1).AddMilliseconds(-1);
            }
            else
            {
                return dateTime;
            }
        }
        /// <summary>
        /// 最小时间
        /// </summary>
        /// <param name="dateTime"></param>
        /// <returns></returns>
        public static DateTime? GetMinDateTime(DateTime? dateTime)
        {
            if (dateTime.HasValue)
            {
                return dateTime.Value.Date;
            }
            else
            {
                return dateTime;
            }
        }

        #endregion
    }