C#中跨数据库增删改的事务控制

http://www.cnblogs.com/gossip/archive/2009/02/16/1392028.html

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类

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;
}