关于C#程序无法取得sqlserver的output参数

cmd.Parameters.Add("@TotalRecords", SqlDbType.Int);
                cmd.Parameters["@TotalRecords"].Direction = ParameterDirection.Output;
                reader = cmd.ExecuteReader();
                while (reader.Read())
                {
                    //...
                }
                TotalRecords = Convert.ToInt32(cmd.Parameters["@TotalRecords"].Value);

DataReader对象是独占连接的，不关DataReader返回参数值取不出来的
所以在TotalRecords = Convert.ToInt32(cmd.Parameters["@TotalRecords"].Value);前必须先把reader关闭

cmd.Parameters.Add("@TotalRecords", SqlDbType.Int);
                cmd.Parameters["@TotalRecords"].Direction = ParameterDirection.Output;
                reader = cmd.ExecuteReader();
                while (reader.Read())
                {
                    //...
                }
                reader.Close();
                TotalRecords = Convert.ToInt32(cmd.Parameters["@TotalRecords"].Value);