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copied!<p>FWIW, it is possible. Here's some code:</p> <p>This would be a dll that you create, then call the HookKeyboard method from your application. I've tested it and it works. Granted, if someone takes a picture with a camera it can't help, but, point made. NYAH!</p> <pre><code> namespace KeyboardHook { public class Hooker { [StructLayout(LayoutKind.Sequential)] public struct KBDLLHOOKSTRUCT { public int vkCode; public int scanCode; public int flags; public int time ; public int extraInfo; } public delegate int HookProc(int nCode, int wParam, IntPtr ptrKBDLLHOOKSTRUCT); [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall, SetLastError = true)] public static extern IntPtr SetWindowsHookEx(int idHook, HookProc callBack, IntPtr hMod, int threadId); [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall, SetLastError = true)] public static extern int CallNextHookEx(IntPtr hhk, int nCode, int wParam, IntPtr lParam); private static IntPtr kbh_Handle; private static HookProc kbh_HookProc; private const int VK_SNAPSHOT = 0x2C; private const int WM_KEYDOWN = 0x0100; private const int WM_SYSKEYDOWN = 0x0104; private const int WH_KEYBOARD_LL = 13; private static int LowLevelKeyboardProc(int nCode, int wParam, IntPtr lParam) { if (nCode < 0) { CallNextHookEx(kbh_Handle, nCode, wParam, lParam); return 0; } if (wParam == WM_KEYDOWN) { IntPtr kbdll = lParam; KBDLLHOOKSTRUCT kbdllstruct = (KBDLLHOOKSTRUCT)Marshal.PtrToStructure(kbdll, typeof(KBDLLHOOKSTRUCT)); if (kbdllstruct.vkCode == VK_SNAPSHOT) return -1; } return CallNextHookEx(kbh_Handle, nCode, wParam, lParam); } public static void HookKeyboard() { try { kbh_HookProc = LowLevelKeyboardProc; kbh_Handle = SetWindowsHookEx(WH_KEYBOARD_LL, kbh_HookProc, Marshal.GetHINSTANCE(Assembly.GetExecutingAssembly().GetModules()[0]), 0); if (kbh_Handle != IntPtr.Zero) System.Diagnostics.Debug.WriteLine(String.Format("It worked! HookHandle: {0}", kbh_Handle)); else { throw new Win32Exception(Marshal.GetLastWin32Error()); } } catch (Exception ex) { System.Diagnostics.Debug.WriteLine(String.Format("ERROR: {0}", ex.Message)); } } } } </code></pre>

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