1\每天从1~999999 累加2\如何处理持久化public class NewNumber
    {
        private static int m_NewID = 0;
        private static DateTime m_NewDatetime = DateTime.Now;
        private static object m_LockHelper = new object();        /// <summary>
        /// 获得一个自增数值
        /// </summary>
        /// <returns></returns>
        public static int GetNewNumber()
        {
            lock (m_LockHelper)
            {
                if (m_NewDatetime.Day != DateTime.Now.Day || m_NewID == 999999)
                {
                    m_NewID = 0;
                }                m_NewID += 1;
            }            return m_NewID;
        }    }