private void Initialize()
{
this.callback = (int nCode, IntPtr wParam, IntPtr lParam) =>
{
HookStruct info = (HookStruct)Marshal.PtrToStructure(lParam, typeof(HookStruct));
bool flag = nCode >= 0 && wParam == (IntPtr)WM_KEYDOWN;
if (flag)
{
int vkCode = Marshal.ReadInt32(lParam);
GlobalKeyPressed?.Invoke(KeyInterop.KeyFromVirtualKey(vkCode));
}
if (LockAllKeys && info.flags != LLKHF_INJECTED)
{
return((IntPtr)1);
}
else
{
return(CallNextHookEx(_hookID, nCode, wParam, lParam));
}
};
_hookID = SetHook(this.callback);
}
/// <summary>
/// A callback function which will be called every Time a keyboard activity detected.
/// </summary>
/// <param name="nCode">
/// [in] Specifies whether the hook procedure must process the message.
/// If nCode is HC_ACTION, the hook procedure must process the message.
/// If nCode is less than zero, the hook procedure must pass the message to the
/// CallNextHookEx function without further processing and must return the
/// value returned by CallNextHookEx.l
/// </param>
/// <param name="wParam">
/// [in] Specifies whether the message was sent by the current thread.
/// If the message was sent by the current thread, it is nonzero; otherwise, it is zero.
/// </param>
/// <param name="lParam">
/// [in] Pointer to a CWPSTRUCT structure that contains details about the message.
/// </param>
/// <returns>
/// If nCode is less than zero, the hook procedure must return the value returned by CallNextHookEx.
/// If nCode is greater than or equal to zero, it is highly recommended that you call CallNextHookEx
/// and return the value it returns; otherwise, other applications that have installed WH_CALLWNDPROC
/// hooks will not receive hook notifications and may behave incorrectly as a result. If the hook
/// procedure does not call CallNextHookEx, the return value should be zero.
/// </returns>
private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam)
{
//indicates if any of underlaing events set e.Handled flag
var handled = false;
if (nCode >= 0)
{
//read structure KeyboardHookStruct at lParam
var keyStruct = (KeyboardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyboardHookStruct));
//raise KeyDown
if (GlobalKeyDown != null && (wParam == WM_KEYDOWN || wParam == WM_SYSKEYDOWN))
{
var keyEventArgs = new GlobalKeyEventHandlerArgs(
keyStruct.VirtualKeyCode,
keyStruct.ScanCode,
keyStruct.Flags,
keyStruct.Time,
keyStruct.ExtraInfo,
null);
GlobalKeyDown.Invoke(null, keyEventArgs);
handled = keyEventArgs.Handled;
}
// raise KeyPress
if (GlobalKeyPressed != null && wParam == WM_KEYDOWN)
{
var isDownShift = ((GetKeyState(VK_SHIFT) & 0x80) == 0x80 ? true : false);
var isDownCapslock = (GetKeyState(VK_CAPITAL) != 0 ? true : false);
var keyState = new byte[256];
GetKeyboardState(keyState);
var inBuffer = new byte[2];
if (ToAscii(keyStruct.VirtualKeyCode,
keyStruct.ScanCode,
keyState,
inBuffer,
keyStruct.Flags) == 1)
{
var key = (char)inBuffer[0];
if ((isDownCapslock ^ isDownShift) && Char.IsLetter(key))
{
key = Char.ToUpper(key);
}
var keyEventArgs = new GlobalKeyEventHandlerArgs(
keyStruct.VirtualKeyCode,
keyStruct.ScanCode,
keyStruct.Flags,
keyStruct.Time,
keyStruct.ExtraInfo,
key);
GlobalKeyPressed.Invoke(null, keyEventArgs);
handled = handled || keyEventArgs.Handled;
}
}
// raise KeyUp
if (GlobalKeyUp != null && (wParam == WM_KEYUP || wParam == WM_SYSKEYUP))
{
var keyEventArgs = new GlobalKeyEventHandlerArgs(
keyStruct.VirtualKeyCode,
keyStruct.ScanCode,
keyStruct.Flags,
keyStruct.Time,
keyStruct.ExtraInfo,
null);
GlobalKeyUp.Invoke(null, keyEventArgs);
handled = handled || keyEventArgs.Handled;
}
}
//if event handled in application do not handoff to other listeners
if (handled)
{
return(-1);
}
//forward to other application
return(CallNextHookEx(_windowsKeyboardHookHandle, nCode, wParam, lParam));
}
