一个自动产生编号的存储过程

一个自动产生编号的存储过程，数据库sql2000或2005 
    //示列.net调用 
 

         /// <summary>
        /// 通过存储过程得到ID号
        /// </summary>
        /// <param name="IDName">编号名称</param>
        /// <param name="IDType">编号类型 1--关联日期如:0706040001 0--自然增长如:0003</param>
        /// <param name="IDLength">编号长度</param>
        public static string getID(string IDName, string IDType, int IDLength)
        {
            SqlConnection conn = new SqlConnection(SqlHelper.ConnStrng);
            string sRef = null;
            try
            {
                SqlCommand cmd = new SqlCommand("p_id", conn);
                cmd.CommandType = CommandType.StoredProcedure;
                SqlParameter parameter = cmd.Parameters.Add("@pName", SqlDbType.VarChar, 20);
                parameter.Value = IDName;

                parameter = cmd.Parameters.Add("@pType", SqlDbType.VarChar, 20);
                parameter.Value = IDType;

                parameter = cmd.Parameters.Add("@pLeng", SqlDbType.Int);
                parameter.Value = IDLength;

                SqlParameter myPara = new SqlParameter("@pValue", SqlDbType.VarChar, 20);
                cmd.Parameters.Add(myPara);
                myPara.Direction = ParameterDirection.Output;