Question

In C#, you can express characters for the KeyPress event in the form Keys.Control | Keys.M. In F#, Keys.Control ||| Keys.M doesn’t work. What does?

Edit: Interesting indeed. Using System.Windows.Forms.Keys.Control ||| System.Windows.Forms.Keys.M as per Johannes Rössel’s suggestion below in the F# interactive window works exactly as he shows. Writing it in a .fs file:

    form.KeyPress.Add (fun e ->
         if (e.KeyChar = (System.Windows.Forms.Keys.Control ||| System.Windows.Forms.Keys.M)) then textbox.SelectAll() )

gives me the error The type 'char' does not support any operators named '|||'. So I probably misidentified the location of the problem. There is no typecasting from Keys to char.

Answer 1

Use +:

Keys.Control + Keys.M

FWIW, ||| works for me, though:

> System.Windows.Forms.Keys.Control ||| System.Windows.Forms.Keys.M;;
val it : System.Windows.Forms.Keys = M, Control