DELPHI实现键盘勾子

//调用键盘钩子，屏蔽功能键
function keyHookProc(nCode: Integer; LWParam: WPARAM; LLParam: LPARAM): LRESULT; stdcall; 
  
var
  hHk :HHOOK;
  
//创建勾子
hHk:= SetWindowsHookEx(13, @keyHookProc, HInstance, 0);

function keyHookProc(nCode: Integer; LWParam: WPARAM; LLParam: LPARAM): LRESULT;//调用键盘钩子，屏蔽功能键
var
  p: PKBDLLHOOKSTRUCT;
  y: integer;
begin
   if nCode < 0 then
  begin
    Result:= CallNextHookEx(hHk, nCode, LWParam, LLParam);
    Exit;
  end
  else
  begin
    y := 0;
    case LWParam of
      WM_KEYDOWN, WM_SYSKEYDOWN, WM_KEYUP,WM_SYSKEYUP:
      begin
        p:= PKBDLLHOOKSTRUCT(LLParam);
        if p^.vkCode = VK_LWIN then y:= 1
        else if p^.vkCode = VK_RWIN then y:= 1
        else if (p.vkCode = VK_RETURN) and ((p.flags and (KF_ALTDOWN shr 8)) <> 0)
          and ((GetKeyState(VK_CONTROL) and $8000) <> 0) then y:= 1
        else if (p.vkCode = VK_ESCAPE) and ((GetKeyState(VK_CONTROL) and $8000) <> 0) then y:= 1
        else if (p.vkCode = VK_ESCAPE) and ((GetKeyState(VK_MENU) and $8000) <> 0) then y:= 1
        else if (p.vkCode = 192) and ((GetKeyState(VK_CONTROL) and $8000) <> 0) then y:= 1
        else if (p.vkCode = VK_TAB) and ((GetKeyState(VK_MENU) and $8000) <> 0) then y:= 1;
      end;
    end;
    if y=1 then
    Result:=1 //如果为WIN功能键则屏蔽
    else
    Result:= CallNextHookEx(hHk, nCode, LWParam, LLParam); //其他键放下一个钩子
  end
end;


//卸载勾子
UnHookWindowsHookEx(hHk);