OpenFileDialog.ShowDialog() throws an exception?

Question

I am trying to show a dialog from one of my WPF view model commands however when i call ShowDialog() it throws a System.ArgumentException, I was wonder

Answer 1

Because ShowDialog() itself returns a Nullable(Of Boolean) and your If statement is expecting a non-Nullable Boolean.

You'll have to cast the dialog's return value to a Boolean and if it's True retreive the selected file through your dialog's Filename property.

Example.