VSTO应用程序中加入键盘钩子

KeyboardHook hook;
private void ThisAddIn_Startup( object sender, System.EventArgs e)
{
hook = new KeyboardHook();
hook.InitHook();
}

private void ThisAddIn_Shutdown( object sender, System.EventArgs e)
{
hook.UnHook();
}
}
// 钩子具体处理逻辑是：
class KeyboardHook
{
#region (invokestuff)
[DllImport( " kernel32.dll " )]
static extern uint GetCurrentThreadId();
[DllImport( " user32.dll " )]
static extern IntPtr SetWindowsHookEx( int code, HookProcKeyboard func, IntPtr hInstance, uint threadID);
[DllImport( " user32.dll " )]
static extern bool UnhookWindowsHookEx(IntPtr hhk);
[DllImport( " user32.dll " )]
static extern int CallNextHookEx(IntPtr hhk, int nCode, IntPtr wParam, IntPtr lParam);
#endregion

#region constans
private const int WH_KEYBOARD = 2 ;
private const int HC_ACTION = 0 ;
#endregion

delegate int HookProcKeyboard( int code, IntPtr wParam, IntPtr lParam);
private HookProcKeyboard KeyboardProcDelegate = null ;
private IntPtr khook;
bool doing = false ;

public void InitHook()
{
uint id = GetCurrentThreadId();
// init the keyboard hook with the thread id of the Visual Studio IDE
this .KeyboardProcDelegate = new HookProcKeyboard( this .KeyboardProc);
khook = SetWindowsHookEx(WH_KEYBOARD, this .KeyboardProcDelegate, IntPtr.Zero, id);
}

public void UnHook()
{
if (khook != IntPtr.Zero)
{
UnhookWindowsHookEx(khook);
}
}

private int KeyboardProc( int code, IntPtr wParam, IntPtr lParam)
{
try
{
if (code != HC_ACTION)
{
return CallNextHookEx(khook, code, wParam, lParam);
}

if (( int )wParam == ( int )Keys.Z && (( int )lParam & ( int )Keys.Alt) != 0 )
{
if ( ! doing)
{
doing = true ;
MessageBox.Show( " Captured " );
doing = false ;
}
}
}
catch
{
}

return CallNextHookEx(khook, code, wParam, lParam);
}
}