Question

我在vb.net和Oracle数据库中有一个项目。当用户密码在oracle中过期时导致oracle exeption。我处理该异常（打开一个ChangePassword表单并更改密码）但是当我发现错误时，我正在丢失我准备执行的程序：
例如：

  Try
            conn = New OracleConnection
            conn.ConnectionString = gApp.ConnectString
            conn.Open()

          'Let's say that error appears here, I want to retun here after password has been changed

            cmd.Connection = conn
            cmd.CommandText = "Delete_Transaction"
            cmd.CommandType = CommandType.StoredProcedure
            OracleCommandBuilder.DeriveParameters(cmd)
            cmd.Parameters("in_transaction_id").Value = TransactionId
            cmd.ExecuteNonQuery()
            conn.Close()


        Catch ex As OracleException
           'PseudoCode:  if error is PasswordExpired->open the ChengePassForm...blah,blah
           'is handled by a Error class that i have
        Finally
            If Not conn Is Nothing Then
                conn.Dispose()
            End If
        End Try

主要问题是问题可能出现在代码的各处，我指的是不同的程序，不同的形式等所以我需要通用的解决方案。实际上我甚至无法想象一个正确的逻辑来接近这个？有谁能告诉我一个方向？

Answer 1

您可以创建一个Action(Of OracleCommand)。

的函数

在Try Catch块中调用委托，如果密码更改，只需再次调用该操作以使用正确的密码重新运行代码。

您可以使用lambda表达式调用此函数请注意lambda表达式中的所有内容可能会多次运行。

Answer 2

使用嵌套的try catch语句：

Try
    Try
        conn = New OracleConnection
        conn.ConnectionString = gApp.ConnectString
        conn.Open()

        'Let's say that error appears here, I want to retun here after password has been changed
    Catch ex1 As OracleException
       'PseudoCode:  if error is PasswordExpired->open the ChengePassForm...blah,blah
       'is handled by a Error class that i have
    Catch ex2 As Exception
        ' throw ex2 to be handled by the parent try catch
    End Try

    cmd.Connection = conn
    cmd.CommandText = "Delete_Transaction"
    cmd.CommandType = CommandType.StoredProcedure
    OracleCommandBuilder.DeriveParameters(cmd)
    cmd.Parameters("in_transaction_id").Value = TransactionId
    cmd.ExecuteNonQuery()
    conn.Close()


Catch ex As Exception
   'PseudoCode:  if error is PasswordExpired->open the ChengePassForm...blah,blah
   'is handled by a Error class that i have
Finally
    If Not conn Is Nothing Then
        conn.Dispose()
    End If
End Try

密码已过期

2 个答案: