Using keyboard hooks for non-windows applications C#

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I want to be able to get keyboard input from games. (I.e. Warcraft 3)
Then based on this input, send keyboard commands back to the game. The game is fullscreen.
I am currently using GetAsyncKeyState() on a timer to tell me what key was last pressed. But then I cant tell if the same key has been pressed twice because the last key pushed will remain the same.
I need to add an event listener somehow for when a key is pushed, instead of a timer to solve that problem, but don't know how.

To send keys back, I was trying to use SendKeys(), but found out it only works on windows related applications?
I don't know if SendInput() is the same?
Sorry if this doesn't make sense, I've tried lots of googling, and it is frustrating.

Posted 7-Jul-12 4:04am

Member 8791890

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[no name] 7-Jul-12 10:25am

Non windows and you are using C#? First thing you need to do is forget C# and start learning C++. Then once you have mastered C++ then start learning about global keyhooks.

Sergey Alexandrovich Kryukov 7-Jul-12 11:35am

This is not really about the language, but yes, it's good to know OS basics, native platform, and there is no a way to use a global hook in .NET only. I explain it in my answer.
--SA

Member 8791890 7-Jul-12 10:43am

I should have been more clear, I am using windows 7. I meant the program itself doesn't have forms and doesn't accept messages from SendKeys(). If I do I get the error, SendKeys cannot run inside this application because the application is not handling Windows messages. Don't really fancy learning another language.

[no name] 7-Jul-12 13:53pm

It is a windows program. What else do you think it could be?

Regardless you cannot install a global hook using .NET.

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Sergey Alexandrovich Kryukov · Answer 1 · 2012-07-07T05:33:00

No, SendInput is not the same, by far. In brief, SendKeys is very limited (I would say, it's pretty much useless, typically used by some loosers as a workaround on the same application they write if they don't know how to write UI in a legitimate way :-)). As to the SendInput, it is very low-level. When you call it, the input is dispatched to some active window, no matter what it is.

You can easily use this function in C# through P/Invoke, because all the hard work is already done for you. Here:
http://www.pinvoke.net/default.aspx/user32/SendInput.html[^].

The approach alternative to P/Invoke is using C++/CLI. You can create a mixed-mode (managed+unmanaged) project, use any C++ unmanaged API, wrap all the unmanaged code in C++/CLI "ref" or "value" classes/structures and make the public. The output of such project can be uses as a regular .NET assembly, for example, referenced by your C# project.

I hope you understand that using raw Windows API through P/Invoke or C++/CLI breaks platform compatibility of your application.

[EDIT]

You can install a Windows Hook in C# project, but you cannot install it as a global hook. According to Microsoft documentation, the hook should be installed in a separate DLL. It should be an unmanaged DLL, of course.

—SA