What is the best platform on which to learn C# - a desktop based approach or a web ASP.NET approach? [on hold]

My goal is to learn C# in depth. What is the best platform or software stack to use to do this? Most detailed C# courses seem to be based on traditional desktop development (WinForms, WPF, etc). With web development growing so fast, however, would it be better to learn in an ASP.NET web environment even if it meant having to learn some additional front end technologies and platforms?