用到3个API函数
BOOL RegisterHotKey(
HWND hWnd, //响应该热键的窗口句柄
Int id, //该热键的唯一标识
UINT fsModifiers, //该热键的辅助按键
UINT vk //该热键的键值
);
为了得到唯一标识,我们还将用到另一个API函数
ATOM GlobalAddAtom(
LPCTSTR lpString //自己设定的一个字符串
);
因为我们还要在程序退出的时候,消除这个热键, 所以需要声明一个全局变量:
HotKeyId: Integer;
第一步:
在窗口的create事件中,加入以下代码
HotKeyId := GlobalAddAtom(‘MyHotKey’) - $C000;
注: HotKeyId的合法取之范围是0x0000到0xBFFF之间, GlobalAddAtom函数得到的值
在0xC000到0xFFFF之间,所以减掉0xC000来满足调用要求。
第二步:
在上面的代码下面加入:
RegisterHotKey(Handle, hotkeyid, MOD_ALT, VK_F8);
热键的辅助按键包括Mod_Ctrl 、Mod_Alt、Mod_Shift,对于Windows兼容键盘还支持Windows
键,即其键面上有Windows标志的那个键,其值为Mod_win。
上面 的代码注册了一个热键:ALT+F8。当然如果你希望象TAKEIT那样,只用F8, 就这么写:
RegisterHotKey(Handle, hotkeyid, 0, VK_F8);
注:handle是一个特殊的变量,它表示当前窗口的句柄。
这个函数你应该能句举一反三了吧。
原理:
一旦热键设置成功,在程序应用过程中如果有相应的键被按下,Windows系统都会给你的应
用程序发送一个消息WM_HOTKEY,不管你的应用程序是否为当前活动的。其中WM_HOTKEY消
息的格式为:
idHotKey = (int) wParam; // 该参数在设置系统级的热键有用,一般不予使用
fuModifiers = (UINT) LOWORD(lParam); //热键的辅助按键
uVirtKey = (UINT) HIWORD(lParam); //热键的键值
第三步:
注册了热键,就该写下响应代码了。
首先,在程序头部分的private段中加入声明 (作用是声明这个过程,和声明变量类似。
关于如何声明函数、过程,请请参考各自的帮助文件或其它资料):
procedure HotKeyDown(var Msg: Tmessage); message WM_HOTKEY;
然后在程序中加入如下代码:
procedure Tfmain.HotKeyDown(var Msg: Tmessage); begin if (Msg.LparamLo = MOD_ALT) AND Msg.LParamHi = VK_F8 then // 假设热键为ALT+F8 begin end; end;
最后一步:
在窗口的close事件中加入
UnRegisterHotKey(handle, HotKeyId); //注销HotKey, 释放资源。
-----------------------------------------------------------------------------------------------
一个实际的例子!
type
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
procedure FormDestroy(Sender: TObject);
protected
procedure hotykey(var msg:TMessage); message WM_HOTKEY;
end;
var
Form1: TForm1;
id,id2:Integer;
implementation
{$R *.DFM}
procedure TForm1.hotykey(var msg:TMessage);
begin
if (msg.LParamLo=MOD_CONTROL) and (msg.LParamHi=81) then
begin
ShowMessage('Ctrl + Q ');
end;
if (msg.LParamLo=MOD_CONTROL) and (msg.LParamHi=82) then
begin
ShowMessage('Ctrl + R ');
end;
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
id:=GlobalAddAtom('hotkey');
ReGISterHotKey(handle,id,mod_control,81);
id2:=GlobalAddAtom('hotkey2');
RegisterHotKey(handle,id2,mod_control,82);
end;
procedure TForm1.FormDestroy(Sender: TObject);
begin
UnRegisterHotKey(handle,id);
UnRegisterHotKey(handle,id2);
end;
附虚键码:
Virtual Key Code Corresponding key
VK_LBUTTON Left mouse button
VK_RBUTTON Right mouse button
VK_CANCEL Control+Break
VK_MBUTTON Middle mouse button
VK_BACK Backspace key
VK_TAB Tab key
VK_CLEAR Clear key
VK_RETURN Enter key
VK_SHIFT Shift key
VK_CONTROL Ctrl key
VK_MENU Alt key
VK_PAUSE Pause key
VK_CAPITAL Caps Lock key
VK_KANA Used with IME
VK_HANGUL Used with IME
VK_JUNJA Used with IME
VK_FINAL Used with IME
VK_HANJA Used with IME
VK_KANJI Used with IME
VK_CONVERT Used with IME
VK_NONCONVERT Used with IME
VK_ACCEPT Used with IME
VK_MODECHANGE Used with IME
VK_ESCAPE Esc key
VK_SPACE Space bar
VK_PRIOR Page Up key
VK_NEXT Page Down key
VK_END End key
VK_HOME Home key
VK_LEFT Left Arrow key
VK_UP Up Arrow key
VK_RIGHT Right Arrow key
VK_DOWN Down Arrow key
VK_SELECT Select key
VK_PRINT Print key (keyboard-specific)
VK_EXECUTE Execute key
VK_SNAPSHOT Print Screen key
VK_INSERT Insert key
VK_DELETE Delete key
VK_HELP Help key
VK_LWIN Left Windows key (Microsoft keyboard)
VK_RWIN Right Windows key (Microsoft keyboard)
VK_APPS Applications key (Microsoft keyboard)
VK_NUMPAD0 0 key (numeric keypad)
VK_NUMPAD1 1 key (numeric keypad)
VK_NUMPAD2 2 key (numeric keypad)
VK_NUMPAD3 3 key (numeric keypad)
VK_NUMPAD4 4 key (numeric keypad)
VK_NUMPAD5 5 key (numeric keypad)
VK_NUMPAD6 6 key (numeric keypad)
VK_NUMPAD7 7 key (numeric keypad)
VK_NUMPAD8 8 key (numeric keypad)
VK_NUMPAD9 9 key (numeric keypad)
VK_MULTIPLY Multiply key (numeric keypad)
VK_ADD Add key (numeric keypad)
VK_SEPARATOR Separator key (numeric keypad)
VK_SUBTRACT Subtract key (numeric keypad)
VK_DECIMAL Decimal key (numeric keypad)
VK_DIVIDE Divide key (numeric keypad)
VK_F1 F1 key
VK_F2 F2 key
VK_F3 F3 key
VK_F4 F4 key
VK_F5 F5 key
VK_F6 F6 key
VK_F7 F7 key
VK_F8 F8 key
VK_F9 F9 key
VK_F10 F10 key
VK_F11 F11 key
VK_F12 F12 key
VK_F13 F13 key
VK_F14 F14 key
VK_F15 F15 key
VK_F16 F16 key
VK_F17 F17 key
VK_F18 F18 key
VK_F19 F19 key
VK_F20 F20 key
VK_F21 F21 key
VK_F22 F22 key
VK_F23 F23 key
VK_F24 F24 key
VK_NUMLOCK Num Lock key
VK_SCROLL Scroll Lock key
VK_LSHIFT Left Shift key (only used with GetAsyncKeyState and GetKeyState)
VK_RSHIFT Right Shift key (only used with GetAsyncKeyState and GetKeyState)
VK_LCONTROL Left Ctrl key (only used with GetAsyncKeyState and GetKeyState)
VK_RCONTROL Right Ctrl key (only used with GetAsyncKeyState and GetKeyState)
VK_LMENU Left Alt key (only used with GetAsyncKeyState and GetKeyState)
VK_RMENU Right Alt key (only used with GetAsyncKeyState and GetKeyState)
VK_PROCESSKEY Process key
VK_ATTN Attn key
VK_CRSEL CrSel key
VK_EXSEL ExSel key
VK_EREOF Erase EOF key
VK_PLAY Play key
VK_ZOOM Zoom key
VK_NONAME Reserved for future use
VK_PA1 PA1 key
VK_OEM_CLEAR Clear key