VB.NET 如果抛出异常，SqlConnection 是否会在 Try/Catch 中自动关闭？

Question

没有找到这个确切的问题/答案。在 VB.NET 中，如果我在 Try/Catch 块中打开 SqlConnection，并且抛出异常(正确捕获)，连接是否隐式关闭，还是必须关闭它？ (如果尝试失败，它甚至会被打开吗？)

会自己“测试”这个，但我真的不知道如何在抛出异常时判断连接是打开还是关闭。

谢谢!

Answer 1

号这就是为什么您需要在 try/catch 之前声明连接变量并向其添加 finally 以确保您有一个可以关闭和处理连接的地方:

 Dim con As New SqlClientConnection( . . .)

 Try
      ' DB Operations (create, read, update, delete) here
      con.open()

 Catch SqlClientException (ex)

     ' Deal with exception
 Finally
      ' Code here will always run, whether or not the try code succeeded
      ' or if you wound up in a catch block. You can safely call .close()
      ' or (as shown below) .dispose() because if the connection is already
      ' closed/disposed, the call doesn't do anything.


      ' Dispose is what you want - it will not only close the
      ' connection, but it will release the .NET reference to
      ' the remote resource, freeing up that resource (the database
      ' in this case) to serve other clients.

      con.Dispose()

 End Try