问设置tMemo顶部项

EN

Memo.Lines.SelStart:=0; 
Memo.Lines.SelLength:=1;

// Trying to get a tMemo to display its contents, starting at the first line.
// Various ideas from assorted net sites, and Peter Below's reply to someone
// with a similar problem - thanks, Peter!
// A couple of bits left in for people to puzzle over as to why they do or don't work!!

uses Winapi.Windows, Winapi.Messages;

var
   KeyStateBefore, KeyStateUse : tKeyboardState;
begin
      PostMessage(MemoPopup.Handle, WM_KeyDown, ord('A'), 0); //'a' gets through
      MemoPopup.Perform(WinApi.Messages.WM_KEYDOWN, ord('K'), 0);  //This does not

      Application.ProcessMessages;


      GetKeyboardState(KeyStateBefore);

      KeyStateUse := KeyStateBefore;
      KeyStateUse[vk_Control] := $81;
      SetKeyBoardState(KeyStateUse); //Now turn on the control key.

      //These do appear to work as expected.
      MemoPopup.Perform(WinApi.Messages.WM_KEYDOWN, vk_Home, 0);
      MemoPopup.Perform(WinApi.Messages.WM_KEYUP, vk_Home, 0);

      Application.ProcessMessages;


      SetKeyboardState(KeyStateBefore); //Remove the control key.

      PostMessage(MemoPopup.Handle, WM_KeyDown, ord('B'), 0); //Got through, lower      case
      MemoPopup.Perform(WinApi.Messages.WM_KEYDOWN, ord('E'), 0);  //Nope

      Application.ProcessMessages;

      KeyStateUse := KeyStateBefore;
      KeyStateUse[vk_Shift] := $80;
      SetKeyboardState(KeyStateUse);

      PostMessage(MemoPopup.Handle, WM_KeyDown, ord('C'), 0); //Got through in   upper case
      MemoPopup.Perform(WinApi.Messages.WM_KEYDOWN, ord('Q'), 0); //Not this though

      Application.ProcessMessages;

      SetKeyBoardState(KeyStateBefore);
      Application.ProcessMessages;

end;