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  • 快数据库事务 .net

    在程序的开发过程中,对数据库的增删改通常要用到事务,用来实现的全部更新和全部回滚。单数据库还比较好做,如果遇到同时操作多个数据库增删改,可以用下面的方法

     一。TransactionScope

         TransactionScope类是framework2.0 新增的一个类,在System.Transactions命名空间中,使用时必须先添加System.Transactions引用;另外还要在windows控制面版-->管理工具-->服务-->Distributed Transaction Coordinator-->属性-->启动,启动这个服务.示例代码如下:


      try
                {
                    
    using (TransactionScope scope = new TransactionScope())
                    {
                        
    //更新northwind数据库的Employees表
                        using (SqlConnection conOne = new SqlConnection("server=.;uid=sa;pwd=123;database=northwind"))
                        {
                            conOne.Open();

                            SqlCommand command 
    = new SqlCommand("update Employees set lastname='chen' where employeeid='1'", conOne);
                            
    int i = command.ExecuteNonQuery();
                        }

                        
    //更新pubs数据库的jobs表
                        using (SqlConnection conTwo = new SqlConnection("server=.;uid=sa;pwd=123;database=pubs"))
                        {
                            conTwo.Open();
                            SqlCommand command 
    = new SqlCommand("update jobs set job_desc='chen' where job_id='1'", conTwo);
                            
    int i = command.ExecuteNonQuery();
                        }

                        scope.Complete();  
    //提交事物
                    }
                }
                
    catch (Exception ex)       //发生异常后自动回滚
                {

                    
    //throw;
                }

    二。另一种方法就是建立两个事务,两个连接了。代码如下;


        SqlConnection conNorthwind = new SqlConnection("server=.;uid=sa;pwd=123;database=northwind");
                SqlConnection conPubs 
    = new SqlConnection("server=.;uid=sa;pwd=123;database=pubs");

                SqlCommand commandNorthwind 
    = new SqlCommand();
                SqlCommand commandPubs 
    = new SqlCommand();
                
    try
                {
                    conNorthwind.Open();
                    conPubs.Open();

                    
    //更新northwind数据库的Employees表
                    SqlTransaction tranNorthwind = conNorthwind.BeginTransaction();
                    commandNorthwind.Connection 
    = conNorthwind;
                    commandNorthwind.Transaction 
    = tranNorthwind;
                    commandNorthwind.CommandText 
    = "update Employees set lastname='chen' where employeeid='1'";
                    
    int i = commandNorthwind.ExecuteNonQuery();

                    
    //更新pubs数据库的jobs表
                    SqlTransaction tranPubs = conPubs.BeginTransaction();
                    commandPubs.Connection 
    = conPubs;
                    commandPubs.Transaction 
    = tranPubs;
                    commandPubs.CommandText 
    = "update jobs set job_desc='chen' where job_id='1'";
                    
    int k = commandPubs.ExecuteNonQuery();

                    
    //throw new Exception();

                    
    //提交事务
                    commandNorthwind.Transaction.Commit();
                    conNorthwind.Close();

                    commandPubs.Transaction.Commit();
                    conPubs.Close();
                }
                
    catch (Exception ex)
                {

                    
    //回滚事务
                    if (commandNorthwind.Transaction != null && conNorthwind != null)
                    {
                        commandNorthwind.Transaction.Rollback();
                        conNorthwind.Close();
                    }

                    
    if (commandPubs.Transaction!= null && conPubs != null)
                    {
                        commandPubs.Transaction.Rollback();
                        conPubs.Close();
                    }
                    
    //throw;
                }
    
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  • 原文地址:https://www.cnblogs.com/l1pe1/p/2024885.html
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