如何在应用程序中的F1上应用键盘钩 [英] How to apply a keyboardhook on F1 within the application

问题描述

对于我们的应用程序，我们创建了一个在线帮助，客户可以在其中查找有关我们应用程序的信息.他们可以在菜单中找到它，但我也想通过在我们应用程序中的任何位置按F1键来使它可用(因为该键主要用于其他应用程序中的帮助).

For our application we created a Online Help where customers can look up stuff about our application. They can reach this in the menus but I also wanted to make it available by pressing the F1 key where ever you are within our application(since this is mostly used for Help within other applications).

我尝试使用RegisterHotKey函数，但事实证明，这会在整个系统范围内注册热键.当您在我们的应用程序中时，我只希望它打开我们的在线帮助.

I tried using the RegisterHotKey function but as it turns out, this registers the hotkey system wide. I only want it to open our Online Help when you are within our application.

因此，我尝试设置键盘挂钩，但这似乎也适用于整个系统.有没有一种方法可以确保在应用程序中按F1键将其打开，但是当您没有将应用程序聚焦时，该方法就无法打开吗?

So i tried to setup a Keyboard hook but this also seems to apply it system wide. Is there a way to make sure that pressing the F1 key within the application will open it, but not when you don't have the application focused?

编码我尝试过的内容:

procedure WMHotKey(var Msg: TWMHotKey); message WM_HOTKEY;

procedure TZZ_Main_Form.WMHotKey(var Msg: TWMHotKey);
begin
  if Msg.HotKey = HotKeyIDF1 then btOnlineHelpClick(nil);
end;

在FormCreate和FormDestroy中:

Within the FormCreate and FormDestroy:

RegisterHotKey(Handle, HotKeyIDF1, 0, VK_F1);
UnRegisterHotKey(Handle, HotKeyIDF1);

关于键盘挂钩，我尝试过的事情:

Regarding the keyboard hook, what i tried:

  hkHook := SetWindowsHookEx(WH_KEYBOARD,@KeyboardProc,hInstance,GetCurrentThreadID());

function KeyboardProc(Code, wParam, lParam: Integer): Integer;
var
  url: String;
  ShellInfo: TShellExecuteInfo;
begin
  try
    case wParam of
      VK_F1:
      begin
        url := 'ourOnlineHelpLink'
        if url <> '' then
        begin
          FillChar( ShellInfo, SizeOf( TShellExecuteInfo ), 0 );
          ShellInfo.cbSize := SizeOf( TShellExecuteInfo );
          ShellInfo.fMask := SEE_MASK_NOCLOSEPROCESS or SEE_MASK_FLAG_NO_UI or
                         SEE_MASK_FLAG_DDEWAIT;
          ShellInfo.Wnd := HWnd_Desktop;
          ShellInfo.lpVerb := 'OPEN';
          ShellInfo.lpFile := PChar( url );
          ShellInfo.lpParameters := nil;
          ShellInfo.lpDirectory := nil;
          ShellInfo.nShow := sw_ShowNormal;

          ShellExecuteEx( @ShellInfo );
        end;
      end;
    end;
  finally
     Result := -1;
  end;
end;

推荐答案

您可以使用 TApplicationEvents.OnHelp 在应用程序范围内拦截 F1 .

You can intercept the F1 application-wide by using TApplicationEvents.OnHelp.

将组件拖放到您的主窗体上，或在主窗体之前创建的数据模块中.双击事件选项卡上的 OnHelp 事件，并添加类似于以下内容的代码(在Delphi 2007之后，参数类型发生了变化，因此我对这两种方法都提供了支持):

Drop the component on your main form, or in a datamodule that is created before your main form. Double-click the OnHelp event on its events tab, and add code similar to the following (the parameter types changed after Delphi 2007, so I've included support for both):

// Delphi 2007 and earlier
{$IFDEF VER185}
function TMainForm.ApplicationEvents1Help(Command: Word; Data: Integer;
  var CallHelp: Boolean): Boolean;
begin
  CallHelp := False;
  // Call your own procedure to implement help as you'd like
  Result := True;
end;
{$ELSE Greater than D2007}
function TMainForm.ApplicationEvents1Help(Command: Word; Data: NativeInt;
  var CallHelp: Boolean): Boolean;
begin
  CallHelp := False;
  // Call your own procedure to implement help as you'd like
  Result := True;
end;
{$ENDIF}

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