C# Signature:

[DllImport("user32.dll")] public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId);

Alternative Managed API:

The ManagedWindowsApi project (http://mwinapi.sourceforge.net) provides a Hook class and subclasses for Journal hooks, Message hooks and Low-Level hooks.

SetWindowsHookEx on MSDN

MSDN example of a mouse hook in C#: http://support.microsoft.com/default.aspx?scid=kb;en-us;318804#3

MSDN article on hooks in .NET: http://msdn.microsoft.com/msdnmag/issues/02/10/CuttingEdge/

MSDN article on KeyboardProc: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/winui/winui/windowsuserinterface/windowing/hooks/hookreference/hookfunctions/keyboardproc.asp

Stephen Toub entry on low-level keyboard hook in C#: http://blogs.msdn.com/toub/archive/2006/05/03/589423.aspx

Stephen Toub entry on low-level mouse hook on C#: http://blogs.msdn.com/toub/archive/2006/05/03/589468.aspx

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