在窗口中可以，但不知在dll如何弄？
unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs;

type
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
private
{ Private declarations }
//定义全局变量
CTRL_A: INTEGER;
//热键响应函数
procedure HotKeyDown(var Msg: Tmessage); message WM_HOTKEY;

public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.dfm}
procedure TForm1.HotKeyDown(var Msg: Tmessage);
begin
//CTRL+A
if (Msg.LparamLo = MOD_CONTROL) AND (Msg.LParamHi = 65) then //退出
begin
ShowMessage('按了CTRL+A');
end;

end;

procedure TForm1.FormCreate(Sender: TObject);
begin
CTRL_A:=GlobalAddAtom('MyCTRL_A') - $C000;
RegisterHotKey(Handle, CTRL_A, MOD_CONTROL, 65);
end;

procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
//释放热键
UnRegisterHotKey(handle, CTRL_A);
end;

end.

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