C#时间处理相关函数

        /// <summary>
        /// 返回两个时间中的值较大的那个
        /// </summary>
        /// <param name="dt1"></param>
        /// <param name="dt2"></param>
        /// <returns></returns>
        public static DateTime GetMaxDateTime(DateTime dt1, DateTime dt2)
        {
            if (dt1 > dt2) return dt1;
            else return dt2;
        }

        /// <summary>
        /// 返回两个时间中的值较小的那个
        /// </summary>
        /// <param name="dt1"></param>
        /// <param name="dt2"></param>
        /// <returns></returns>
        public static DateTime GetMinDateTime(DateTime dt1, DateTime dt2)
        {
            if (dt1 < dt2) return dt1;
            else return dt2;
        }

        /// <summary>
        /// 将格式为"HH:mm:ss"的字符串转换为TimeSpan类型
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        public static TimeSpan StrToTimeSpan(string str)
        {
            string[] strArray = str.Split(':');
            if (strArray.Length != 3) return new TimeSpan(0, 0, 0);
            return new TimeSpan(Convert.ToInt32(strArray[0]), Convert.ToInt32(strArray[1]), Convert.ToInt32(strArray[2]));
        }

        /// <summary>
        /// 将分钟数转换为HH:mm表示的字符串
        /// </summary>
        /// <param name="minutes"></param>
        /// <returns></returns>
        public static string ConvertMinutes(object obj)
        {
            if (obj == null || obj == DBNull.Value) return "00:00";

            int time = Convert.ToInt32(obj);
            int hour = time / 60;//取整
            int minute = time % 60;//求余
            string strValue = string.Format("{0}:{1}", hour, minute);

            return strValue;
        }