代码如下：

        /// <summary>
        /// 事务测试
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        public int ServiceTest(string str)
        {

            int ret=0;

            using (OdbcConnection conn = new OdbcConnection(str))
            {
                conn.Open();
                OdbcCommand command = conn.CreateCommand();
                OdbcTransaction transaction;
                //启动事务
                transaction =  conn.BeginTransaction();

                command.Connection = conn;
                command.Transaction = transaction;

                try
                {
                    //获取插入数据后的ID
                    command.CommandText = "insert into com_user (`username`,`password`,`logintime`,`loginip`,`lock`) values('bbb','bbb',222,'bbb',0);SELECT LAST_INSERT_ID();";//SELECT LAST_INSERT_ID()是mysql提供的方法
                    int aa = command.ExecuteNonQuery();
                    //获取插入的ID
                    int newId = Convert.ToInt32(command.ExecuteScalar());
                    //下面的sql语句是错误的,为了catch错误回滚

                    command.CommandText = "insert into com_user_1 (`username`,`password`,`logintime`,`loginip`,`lock`) values('aaa','aaa',111,'aaa',0)";
                    command.ExecuteNonQuery();

                    transaction.Commit();
                }
                catch (Exception ex)
                {
                    transaction.Rollback();

                    ret = -1;
                }
                finally
                {
                    conn.Close();
                }
            }
            return ret;
        }

1、刚开始的时候事务无法回滚，主要原因是数据库表引擎设置问题，需要设置成InnoDB模式。

2、数据库表结构：。