Question

I don’t have an XP machine handy. If I use the Windows API Codepack to do something new to Vista/Win7 (e.g. “TaskDialog”) in C#, how does it cope with running on Windows XP machines?

If I use the Codepack, have I effectively made my application only support Vista and later versions of Windows?

Answer 1

If you look into “TaskDialog.cs”, you will find that TastDialog’s constructor includes the following lines:

// Throw PlatformNotSupportedException if the user is not running Vista or beyond
CoreHelpers.ThrowIfNotVista();

If you only include a reference to the Windows API Code Pack assembly, you will be fine. But using a feature which is not present on the OS currently running your application will throw an exception. To check if a feature is safe to call (i.e. supported on the current OS) most classes include a static IsPlatformSupported property.

So you could check TaskDialog.IsPlatformSupported first and call MessageBox.Show() instead if your OS doesn’t support TaskDialogs.