Question: Ive seen many solutions online but none does exactly what I want. What is the best/simplest way to get any keys pressed in a given process (not my console applicaton) while my application is running in background. I dont need the modifiers or anything.

Answer: 
Oh, so you're looking for "Autofire" in old-school gaming terms?

Instead of writing your own keyboard hook app (unless you're doing it for fun/the thrill of it/the exercise) you might want to look at AutoIt or AutoHotkey, which are both pretty good for keyboard/mouse automation.

See this thread for instance... <http://www.autohotkey.com/board/topic/40598-autofire-keyboard/>
I have found a way to hook only for a process.
You may need it.

```
int ProcessId = GetProcessesByName("Your_app_here").FirstOrDefault().Id;
private IntPtr SetHook(KeyboardHookHandler proc)
    {
        return SetWindowsHookEx(13, proc, GetModuleHandle(Process.GetProcessById(ProcessId).MainModule.ModuleName), GetWindowThreadProcessId(GetModuleHandle(Process.GetProcessById(ProcessId).MainModule.ModuleName), out int MainThreadId));
    }

```

Remember to import these methods.

```
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    private static extern IntPtr SetWindowsHookEx(int idHook, KeyboardHookHandler lpfn, IntPtr hMod, uint dwThreadId);

[DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    private static extern IntPtr GetModuleHandle(string lpModuleName);

[DllImport("user32.dll", SetLastError = true)]
    static extern uint GetWindowThreadProcessId(IntPtr hWnd, out int lpdwProcessId);

```