How can I toggle fullscreen for the embedded VLC player - vb.net

Question

I am embedding the VLC media player into a Windows Forms application through an activeX control.
The code goes like this:
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
'Open file button
Dim openFileDialog1 As New OpenFileDialog()
openFileDialog1.Title = "Open file"
If openFileDialog1.ShowDialog() = Windows.Forms.DialogResult.OK Then
AxVLCPlugin21.playlist.add(openFileDialog1.FileName)
End If
openFileDialog1.Dispose()
End Sub
Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
'Play button
AxVLCPlugin21.playlist.play()
End Sub
Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
'Stop button
AxVLCPlugin21.playlist.stop()
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
'Pause button
AxVLCPlugin21.playlist.togglePause()
End Sub
Private Sub TrackBar1_Scroll(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TrackBar1.Scroll
'Volume control
AxVLCPlugin21.audio.Volume = TrackBar1.Value
End Sub
Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
'Toggle Full Screen button
AxVLCPlugin21.video.toggleFullscreen()
End Sub
End Class
How can I toggle full screen?
This code makes no effect:
AxVLCPlugin21.video.toggleFullscreen()
Thank you.

Answer 1

if (axVLCPlugin21.video.fullscreen)
axVLCPlugin21.video.fullscreen = false;
else
axVLCPlugin21.video.fullscreen = true;