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copied!<p>As outlined <a href="http://social.msdn.microsoft.com/Forums/en-CA/csharpgeneral/thread/3a048d00-2dbd-4b07-a860-c09bd1e254e9" rel="nofollow">here</a> there is a problem with Windows Forms' ActiveX container support. The keyboard message does not get passed to the Flash player. </p> <p>The solution I've come up with (based on code from <a href="http://social.msdn.microsoft.com/Forums/en-US/winforms/thread/8f573d2c-7ba5-480e-a25d-b2ce608d8b5f/" rel="nofollow">here</a>) is to write a keyboard hook to catch the Escape key and to pass a message to the Flash window to close if it's active.</p> <p>First, there's the <code>KeyHook</code> class which provides the plumbing to listen for the Escape key. </p> <pre><code>using System; using System.Collections.Generic; using System.Diagnostics; using System.Runtime.InteropServices; using System.Windows.Forms; namespace Your.Utility { public class KeyBordHook { private const int WM_KEYDOWN = 0x100; private const int WM_KEYUP = 0x101; private const int WM_SYSKEYDOWN = 0x104; private const int WM_SYSKEYUP = 0x105; //Global event public event KeyEventHandler OnKeyDownEvent; public event KeyEventHandler OnKeyUpEvent; public event KeyPressEventHandler OnKeyPressEvent; private static int hKeyboardHook = 0; private const int WH_KEYBOARD_LL = 13; //keyboard hook constant private HookProc KeyboardHookProcedure; // declare keyhook event type //declare keyhook struct [StructLayout(LayoutKind.Sequential)] public class KeyboardHookStruct { public int vkCode; public int scanCode; public int flags; public int time; public int dwExtraInfo; } [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)] private static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId); [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)] private static extern bool UnhookWindowsHookEx(int idHook); [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)] private static extern int CallNextHookEx(int idHook, int nCode, Int32 wParam, IntPtr lParam); [DllImport("user32")] private static extern int ToAscii(int uVirtKey, int uScanCode, byte[] lpbKeyState, byte[] lpwTransKey, int fuState); [DllImport("user32")] private static extern int GetKeyboardState(byte[] pbKeyState); [DllImport("kernel32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)] private static extern IntPtr GetModuleHandle(string lpModuleName); private delegate int HookProc(int nCode, Int32 wParam, IntPtr lParam); private List<Keys> preKeys = new List<Keys>(); public KeyBordHook() { Start(); } ~KeyBordHook() { Stop(); } public void Start() { //install keyboard hook if (hKeyboardHook == 0) { KeyboardHookProcedure = new HookProc(KeyboardHookProc); //hKeyboardHook = SetWindowsHookEx(WH_KEYBOARD_LL, KeyboardHookProcedure, Marshal.GetHINSTANCE(Assembly.GetExecutingAssembly().GetModules()[0]), 0); Process curProcess = Process.GetCurrentProcess(); ProcessModule curModule = curProcess.MainModule; hKeyboardHook = SetWindowsHookEx(WH_KEYBOARD_LL, KeyboardHookProcedure, GetModuleHandle(curModule.ModuleName), 0); if (hKeyboardHook == 0) { Stop(); throw new Exception("SetWindowsHookEx ist failed."); } } } public void Stop() { bool retKeyboard = true; if (hKeyboardHook != 0) { retKeyboard = UnhookWindowsHookEx(hKeyboardHook); hKeyboardHook = 0; } //if unhook failed if (!(retKeyboard)) throw new Exception("UnhookWindowsHookEx failed."); } private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam) { if ((nCode >= 0) && (OnKeyDownEvent != null || OnKeyUpEvent != null || OnKeyPressEvent != null)) { KeyboardHookStruct MyKeyboardHookStruct = (KeyboardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyboardHookStruct)); if ((OnKeyDownEvent != null || OnKeyPressEvent != null) && (wParam == WM_KEYDOWN || wParam == WM_SYSKEYDOWN)) { Keys keyData = (Keys)MyKeyboardHookStruct.vkCode; if (IsCtrlAltShiftKeys(keyData) && preKeys.IndexOf(keyData) == -1) { preKeys.Add(keyData); } } if (OnKeyDownEvent != null && (wParam == WM_KEYDOWN || wParam == WM_SYSKEYDOWN)) { Keys keyData = (Keys)MyKeyboardHookStruct.vkCode; KeyEventArgs e = new KeyEventArgs(GetDownKeys(keyData)); OnKeyDownEvent(this, e); } if (OnKeyPressEvent != null && wParam == WM_KEYDOWN) { byte[] keyState = new byte[256]; GetKeyboardState(keyState); byte[] inBuffer = new byte[2]; if (ToAscii(MyKeyboardHookStruct.vkCode, MyKeyboardHookStruct.scanCode, keyState, inBuffer, MyKeyboardHookStruct.flags) == 1) { KeyPressEventArgs e = new KeyPressEventArgs((char)inBuffer[0]); OnKeyPressEvent(this, e); } } if ((OnKeyDownEvent != null || OnKeyPressEvent != null) && (wParam == WM_KEYUP || wParam == WM_SYSKEYUP)) { Keys keyData = (Keys)MyKeyboardHookStruct.vkCode; if (IsCtrlAltShiftKeys(keyData)) { for (int i = preKeys.Count - 1; i >= 0; i--) { if (preKeys[i] == keyData) { preKeys.RemoveAt(i); } } } } if (OnKeyUpEvent != null && (wParam == WM_KEYUP || wParam == WM_SYSKEYUP)) { Keys keyData = (Keys)MyKeyboardHookStruct.vkCode; KeyEventArgs e = new KeyEventArgs(GetDownKeys(keyData)); OnKeyUpEvent(this, e); } } return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam); } private Keys GetDownKeys(Keys key) { Keys rtnKey = Keys.None; foreach (Keys keyTemp in preKeys) { switch (keyTemp) { case Keys.LControlKey: case Keys.RControlKey: rtnKey = rtnKey | Keys.Control; break; case Keys.LMenu: case Keys.RMenu: rtnKey = rtnKey | Keys.Alt; break; case Keys.LShiftKey: case Keys.RShiftKey: rtnKey = rtnKey | Keys.Shift; break; default: break; } } rtnKey = rtnKey | key; return rtnKey; } private Boolean IsCtrlAltShiftKeys(Keys key) { switch (key) { case Keys.LControlKey: case Keys.RControlKey: case Keys.LMenu: case Keys.RMenu: case Keys.LShiftKey: case Keys.RShiftKey: return true; default: return false; } } } } </code></pre> <p>Next, you need to create an instance of the <code>KeyHook</code> class in your Windows Form ...</p> <pre><code>// inside Form class ... private readonly KeyBordHook _keyBordHook = new KeyBordHook(); private void InitKeyHook() { _keyBordHook.OnKeyPressEvent += new KeyPressEventHandler(_KeyBordHook_OnKeyPressEvent); _keyBordHook.Start(); } void _KeyBordHook_OnKeyPressEvent(object sender, KeyPressEventArgs e) { if (e.KeyChar == Convert.ToChar(Keys.Escape)) WindowHelper.CloseWindowIfActive("Flash"); } public void StartKeyListening() { InitKeyHook(); } public void StopKeyListening() { _keyBordHook.Stop(); } </code></pre> <p>And, the code to actually close the Flash Window...</p> <pre><code>public sealed class WindowHelper { [DllImport("USER32.dll", SetLastError = true)] private static extern IntPtr GetForegroundWindow(); [DllImport("USER32.dll", SetLastError = true)] private static extern int GetWindowText(IntPtr hWnd, StringBuilder text, int count); static uint WM_CLOSE = 0x10; [return: MarshalAs(UnmanagedType.Bool)] [DllImport("USER32.dll", SetLastError = true)] static extern bool PostMessage(IntPtr hWnd, uint Msg, IntPtr wParam, IntPtr lParam); private static bool CloseWindow(IntPtr hWnd) { bool returnValue = PostMessage(hWnd, WM_CLOSE, IntPtr.Zero, IntPtr.Zero); if (!returnValue) throw new Win32Exception(Marshal.GetLastWin32Error()); return true; } public static void CloseWindowIfActive(string windowTitle) { const int nChars = 256; StringBuilder buff = new StringBuilder(nChars); IntPtr handle = GetForegroundWindow(); if (GetWindowText(handle, buff, nChars) <= 0) return; if (buff.ToString().ToLower().IndexOf(windowTitle.ToLower()) > -1) CloseWindow(handle); } } </code></pre> <p>I'm sure there's improvements to be made in all of the above but so far, this solution appears to work for me.</p> <p><strong>Note</strong> that this code allows you to <em>record all key strokes</em> across all apps so it's definitely overkill and may not be desirable to integrate into a customer bound application!</p>

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