Cannot Set File Path In Text Box Using FileOpendialaog

I'm trying to get the file path by using the FileOpenDialog function, but when i set the value to the textbox , the textbox will be empty

I traced the code and i see that the value is set to the textbox but the form is empty , i don't know why

See the code below:

Private Sub FnOpenFileDialog()
Dim openfile As New System.Windows.Forms.OpenFileDialog
openfile.InitializeLifetimeService()
openfile.Filter = String.Format("Image file (*.jpg)|*.jpg|All files (*.*)|*.*")
openfile.InitialDirectory = "c:"

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