.NET事务的用法

 using (SqlTransaction st = conn.BeginTransaction(IsolationLevel.ReadUncommitted))
                    {
                        //cmd.Transaction = st;
                        try
                        {
                            cmd.ExecuteNonQuery();
                            st.Rollback();
                            conn.Close();
                        }
                        catch (SqlException sqlEx)
                        {
                            st.Rollback();
                            throw sqlEx;
                        }
                    }

在如上代码调试时，出现异常：

  异常提示：

+      [System.InvalidOperationException] {"如果分配给命令的连接位于本地挂起事务中，ExecuteNonQuery 要求命令拥有事务。命令的 Transaction 属性尚未初始化。"}    System.InvalidOperationException

后来，检查发现是缺少了上面代码中“cmd.Transaction = st;”一行。加上即可。