You can get the project guid using IProject.Guid, however, this won't give you want you need. The project guid is a unique identifier for that project, and doesn't provide any information about the type of project. There is a project type guid, and this will tell you if it's C#, VB, F#, or whatever, but again, won't help in your use case. And finally, there are what are known as "flavour" guids. These are the values that go in the
ProjectTypeGuids element in the .csproj file, and are optional. There is a WPF guid (
{60DC8134-EBA5-43B8-BCC9-BB4BC16C2548}) but I don't know when it's used. It is completely possible to create a C# project that uses WPF without using this type guid. And it's perfectly possible, and indeed likely, that a project will include both WPF and WinForms. In other words, I don't think you can tell, just by looking at the project details what the shortcut identifier character is.
Regards
Matt