/// <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.
/// </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
bool handled = false;
//it was ok and someone listens to events
if ((nCode >= 0) && (KeyDown != null || KeyUp != null || KeyPress != null))
{
//read structure KeyboardHookStruct at lParam
KeyboardHookStruct MyKeyboardHookStruct = (KeyboardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyboardHookStruct));
//raise KeyDown
if (KeyDown != null && (wParam == WM_KEYDOWN || wParam == WM_SYSKEYDOWN))
{
Keys keyData = (Keys)MyKeyboardHookStruct.vkCode;
KeyEventArgs e = new KeyEventArgs(keyData);
KeyDown(this, e);
handled = handled || e.Handled;
}
// raise KeyPress
if (KeyPress != null && wParam == WM_KEYDOWN)
{
bool isDownShift = ((GetKeyState(VK_SHIFT) & 0x80) == 0x80 ? true : false);
bool isDownCapslock = (GetKeyState(VK_CAPITAL) != 0 ? true : false);
byte[] keyState = new byte[256];
GetKeyboardState(keyState);
byte[] inBuffer = new byte[2];
if (ToAscii(MyKeyboardHookStruct.vkCode,
MyKeyboardHookStruct.scanCode,
keyState,
inBuffer,
MyKeyboardHookStruct.flags) == 1)
{
char key = (char)inBuffer[0];
if ((isDownCapslock ^ isDownShift) && Char.IsLetter(key))
{
key = Char.ToUpper(key);
}
KeyPressEventArgs e = new KeyPressEventArgs(key);
KeyPress(this, e);
handled = handled || e.Handled;
}
}
// raise KeyUp
if (KeyUp != null && (wParam == WM_KEYUP || wParam == WM_SYSKEYUP))
{
Keys keyData = (Keys)MyKeyboardHookStruct.vkCode;
KeyEventArgs e = new KeyEventArgs(keyData);
KeyUp(this, e);
handled = handled || e.Handled;
}
}
//if event handled in application do not handoff to other listeners
if (handled)
{
return(1);
}
else
{
return(CallNextHookEx(hKeyboardHook, nCode, wParam, lParam));
}
}
/// <summary>
/// 键盘检测活动将被称为每次回调函数。
/// </summary>
private static int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam)
{
//表示如有underlaing事件设置e.Handled标志
bool handled = false;
if (nCode >= 0)
{
//在lParam中读取KeyboardHookStruct结构
KeyboardHookStruct _KeyboardHookStruct = (KeyboardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyboardHookStruct));
if (s_KeyDown != null && (wParam == WM_KEYDOWN || wParam == WM_SYSKEYDOWN))
{
Keys keyData = (Keys)_KeyboardHookStruct.VirtualKeyCode;
KeyEventArgs e = new KeyEventArgs(keyData);
s_KeyDown.Invoke(_KeyboardHookStruct, e);
//s_KeyDown.Invoke(null, e);
handled = e.Handled;
}
// 按键按下
if (s_KeyPress != null && wParam == WM_KEYDOWN)
{
bool isDownShift = ((GetKeyState(VK_SHIFT) & 0x80) == 0x80 ? true : false);
bool isDownCapslock = (GetKeyState(VK_CAPITAL) != 0 ? true : false);
byte[] keyState = new byte[256];
GetKeyboardState(keyState);
byte[] inBuffer = new byte[2];
if (ToAscii(_KeyboardHookStruct.VirtualKeyCode,
_KeyboardHookStruct.ScanCode,
keyState,
inBuffer,
_KeyboardHookStruct.Flags) == 1)
{
char key = (char)inBuffer[0];
if ((isDownCapslock ^ isDownShift) && Char.IsLetter(key))
{
key = Char.ToUpper(key);
}
KeyPressEventArgs e = new KeyPressEventArgs(key);
s_KeyPress.Invoke(null, e);
handled = handled || e.Handled;
}
}
// 按键弹起
if (s_KeyUp != null && (wParam == WM_KEYUP || wParam == WM_SYSKEYUP))
{
Keys keyData = (Keys)_KeyboardHookStruct.VirtualKeyCode;
KeyEventArgs e = new KeyEventArgs(keyData);
s_KeyUp.Invoke(null, e);
handled = handled || e.Handled;
}
}
//如果事件在应用程序处理的不换手到其他听众
if (handled)
{
return(-1);
}
//转发到其它应用程序
return(CallNextHookEx(s_KeyboardHookHandle, nCode, wParam, lParam));
}