Suppress task switch keys (winkey, alt-tab, alt-esc, ctrl-esc) using low-level keyboard hook
- by matt
I'm trying to suppress task switch keys (such as winkey, alt-tab, alt-esc, ctrl-esc, etc.) by using a low-level keyboard hook.
I'm using the following LowLevelKeyboardProc callback:
IntPtr HookCallback(int nCode, IntPtr wParam, ref KBDLLHOOKSTRUCT lParam)
{
if (nCode >= 0)
{
bool suppress = false;
// Suppress left and right windows keys.
if (lParam.Key == VK_LWIN || lParam.Key == VK_RWIN)
suppress = true;
// Suppress alt-tab.
if (lParam.Key == VK_TAB && HasAltModifier(lParam.Flags))
suppress = true;
// Suppress alt-escape.
if (lParam.Key == VK_ESCAPE && HasAltModifier(lParam.Flags))
suppress = true;
// Suppress ctrl-escape.
/* How do I hook CTRL-ESCAPE ? */
// Suppress keys by returning 1.
if (suppress) return new IntPtr(1);
}
return CallNextHookEx(HookID, nCode, wParam, ref lParam);
}
bool HasAltModifier(int flags)
{
return (flags & 0x20) == 0x20;
}
However, I'm at a loss as to how to suppress the CTRL-ESC combination.
Any suggestions? Thanks.