什么是本代码的VB.NET版本？

Question

if (InvokeRequired)
{
  BeginInvoke(new MethodInvoker(delegate()
  {
    textBox1.Text = args.Fax.Port.ToString();
    textBox2.Text = args.Fax.FaxStatus.ToString();
  }));
}

Answer 1

Courtesy of developerfusion.com :

If InvokeRequired Then
    BeginInvoke(New MethodInvoker(Function() Do
        textBox1.Text = args.Fax.Port.ToString()
        textBox2.Text = args.Fax.FaxStatus.ToString()
    End Function))
End If

Answer 2

From MSDN

Delegate Sub MyDelegate(myControl As Label, myArg2 As String)

Private Sub Button_Click(sender As Object, e As EventArgs)
   Dim myArray(1) As Object

   myArray(0) = New Label()
   myArray(1) = "Enter a Value"
   myTextBox.BeginInvoke(New MyDelegate(AddressOf DelegateMethod), myArray)
End Sub 

Public Sub DelegateMethod(myControl As Label, myCaption As String)
   myControl.Location = New Point(16, 16)
   myControl.Size = New Size(80, 25)
   myControl.Text = myCaption
   Me.Controls.Add(myControl)
End Sub 

So

if (InvokeRequired)
{
  BeginInvoke(new MethodInvoker(delegate()
  {
    textBox1.Text = args.Fax.Port.ToString();
    textBox2.Text = args.Fax.FaxStatus.ToString();
  }));
}

Delegate Sub MyDelegate(faxPort As String, faxStatus As String)

If InvokeRequired Then
    Dim aArray(1) as Object
    aArray(0) = args.Fax.Port.ToString()
    aArray(1) = args.Fax.FaxStatus.ToString();
    BeginInvoke(New MyDelegate(AddressOf MySub), aArray)
End If

Sub MySub( faxPort as String, faxStatus as String)
    textBox1.Text = faxPort
    textBox2.Text = faxStatus
End Sub

I think

Answer 3

VB.NET 9 and previous does not support multi line anonymous functions. You need to write a separate function:

If InvokeRequired Then
    BeginInvoke(New MethodInvoker(AddressOf MySub))
End If

where MySub:

Sub MySub()
    textBox1.Text = args.Fax.Port.ToString()
    textBox2.Text = args.Fax.FaxStatus.ToString()    
End Sub

---

UPDATE:

To clarify about the args parameter there's an overload of BeginInvoke that could be used and in this case the MethodInvoker delegate is no longer suitable. Action(Of T) would work:

If InvokeRequired Then
    BeginInvoke(New Action(Of SomeType)(AddressOf MySub), args)
End If

and:

Sub MySub(ByVal args as SomeType)
    textBox1.Text = args.Fax.Port.ToString()
    textBox2.Text = args.Fax.FaxStatus.ToString()    
End Sub

After all it's simple things like this that make C# developers happy :-) (please don't take it wrong, I have nothing against VB.NET)

Answer 4

Until Visual Studio 2010, VB.Net does not support multi-statement anonymous functions.

You need to move the anonymous method into a separate method that takes args as a parameter, then call Invoke on it.

Answer 5

Since the comments do not allow formatting, I'm going to post my working solution here. Thanks to all who chimed in - Darin, SLaks, drachenstern, Jay.

Private Sub myControl_FaxStatus(ByVal sender As Object, ByVal args As DataTech.FaxManNet.FaxEventArgs)
  frmModemStatus.UpdateStatus(args.Fax)

  If InvokeRequired Then
    Dim aArray(1) As Object
    aArray(0) = args.Fax.Port.ToString()
    aArray(1) = args.Fax.FaxStatus.ToString()
    BeginInvoke(New MyDelegate(AddressOf UpdateStatusDisplay), aArray)
  End If

  Try
    TextBox1.Text = args.Fax.Port.ToString()
    TextBox2.Text = args.Fax.FaxStatus.ToString()
  Catch ex As Exception
    System.Diagnostics.Debug.WriteLine("ex = " & ex.ToString())
  End Try

End Sub

Delegate Sub MyDelegate(ByVal faxPort As String, ByVal faxStatus As String)

Private Sub UpdateStatusDisplay(ByVal faxPort As String, ByVal faxStatus As String)
  TextBox1.Text = faxPort
  TextBox2.Text = faxStatus
End Sub

Answer 6

If you need similar stuff in the feature just install the following component to your visual studio. After that you can easly convert from c# to vb.net or vb.net to c#. VS2010 Support is already included. http://codeconvert.codeplex.com/