.NET Application Icon

What size should the Applicati开发者_开发技巧on Icon be for .NET programs?

You can have multiple sizes in single Icon file (XP style icons) and depending on the situation Windows can use the right size from the collection. For more information see this MSDN article.

Edit: Official Windows Icon Guidelines (specifically the size requirements):

Application icons and Control Panel items: The full set includes 16x16, 32x32, 48x48, and 256x256 (code scales between 32 and 256). The .ico file format is required. For Classic Mode, the full set is 16x16, 24x24, 32x32, 48x48 and 64x64.

Using GIMP, you can create an Icon file with all sizes, based on a 256x256 image. Just save your image as "ICO".

http://www.gimp.org/windows/

With Windows Vista and Windows 7 supporting 256x256 icons, that would be your best bet. You can then scale it as needed (and so can Windows).

Stick with a 32x32 .ico at design time, and you'll be fine. Generally .ico can be 16x16.

Icon files (.ico) can have multiple images within them. Those images can be multiple colour depths/sizes. Use a tool like Photoshop or Paint.NET, and you can include 16x16, 32x32, 48x48 and 64x64 in a single .ico file, and the operating system will display the best one to show, depending on the view of the directory (Details, List, Large Icon, etc).