Is there a way to capture HotKeys/Shortcuts in Excel VSTO using only C# and no VBA?

1. One method involves using the 3rd party solution from Addin-Express. Their product includes the ability to add a keyboard shortcut as a property to the ribbon menu commands.

2. The other way is to make use of low level keyboard hooks, through some Win32 API's which is generally referred to as windows subclassing. Here is an excellent explanation with code sample of how to do it. Note that the only "extra" thing you need to do to get this code to "work" in VSTO is moving the SetHook() method to the Startup event, and the UnhookWindowsHookEx() method to the Shutdown event.

   Check out the article on MSDN here by Stephen Toub.

3. Finally there is the use of the OnAction property of the Addin class. This method requires the use of some VBA (in terms of a callback method that points back to the underlying .net addin), and works ok so long as you are willing to distribute some VBA in your solution (i.e. a xls or doc w/ vba project, or perhaps a native addin). Note you will also need to mark comvisible = true, and expose the GetAutomationServiceObject method so that your VBA can reference your addin from VBA code.

   see here for a thread on it...

You can only do this through API calls to subclass Excel and watch for key commands. This is older, but it still applies.