分层 对数据库 事件的回滚和提交 事件

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Data.SqlClient;using System.Data;namespace 事务{    class Program    {        static void Main(string[] args)        {            //连接字符串            string str = "Data Source=.;Initial Catalog=MySchool;Integrated Security=True";            //构建连接对象            SqlConnection con = new SqlConnection(str);            //构建 SQL            string sql = "insert into grade values('S2226')";            //准备命令对象            SqlCommand cmd = new SqlCommand(sql, con);            //打开连接            con.Open();            //创建事务对象 保证连接打开后            SqlTransaction tx = con.BeginTransaction();            //绑定事务属性            cmd.Transaction = tx;            //提交  回滚            try            {                //执行添加                int count = cmd.ExecuteNonQuery();                if (count > 0)                {                    Console.WriteLine("权萌萌   好了");                }                tx.Commit();            }            catch (Exception)            {                tx.Rollback();                        }            //关闭连接            con.Close();            Console.ReadKey();        }    }}