Why is DialogResult a nullable bool in WPF?

Question

Can anyone think of a good explanation for the fact that result of a dialog is a nullable bool in WPF? This has always baffled me. In WinForms it was an enum type and that m

Answer 1

In my opinion this was done because in most cases you don't need the generalized specialized options like Retry or Ignore.

If you need more than OK/Cancel, you are supposed to use some kind of task dialog, e.g. with written-out answers. That way, you're not limited to the few enum values someone thought of some decades ago, and the DialogResult is just positive/negative for basic use and you can implement your own property that is specific to your advanced needs. Therefore only true/false is needed, and null indicating that the window has not been closed yet (no value has been assigned to the property yet).

If you have a dialog that is more than just a question the user should answer (e.g. an entry form), you're typically better off with OK/Cancel, so you don't need more values.