編碼過程中使用SqlDataReader 來操作數據庫時,你是否每次在調用完你的數據庫方法后,再手動調用方法或寫代碼關閉數據庫聯接呢？(呵呵　我以前是這樣做的　見笑)
下面的方法可以完成解決此問題了,cmd.ExecuteReader的參數CommandBehavior.CloseConnection會自動幫你關閉與之相關聯的conn

 public static SqlDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
      {

            SqlCommand cmd = new SqlCommand();

            SqlConnection conn = new SqlConnection(connectionString);

          try
            {

                PRepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);

                   // 給cmd.ExecuteReader加上參數CommandBehavior.CloseConnection會在cmd.ExecuteReader執行完后自動關閉與之相關聯的conn
                SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
               
                cmd.Parameters.Clear();

                return rdr;

            }

            catch
            {

                conn.Close();

                throw;

            }

       }
http://www.survivalescaperooms.com/abeen/archive/2006/12/19/597039.html