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procedure PostKeyEx(hWindow : HWnd; Key : Word; const Shift : TShiftState; SpecialKey : Boolean);
type
  TBuffers = Array[0..1] of TKeyboardState;
var
  pKeyBuffers : ^TBuffers;
  lParam : LongInt;
begin
  if IsWindow(hWindow) then
  begin
    pKeyBuffers := nil;
    lParam := MakeLong(0, MapVirtualkey(Key,0));
    if SpecialKey then lParam := lParam or $1000000;
    New(pKeyBuffers);
    try
      GetKeyboardState(pKeyBuffers^[1]);
      FillChar(pKeyBuffers^[0],SizeOf(TKeyboardState), 0);
      if ssShift in Shift then pKeyBuffers^[0][VK_SHIFT] := $80;
      if ssAlt in Shift then
      begin
        pKeyBuffers^[0][VK_MENU] := $80;
        lParam := lParam or $20000000;
      end;
      if ssCtrl   in Shift then pKeyBuffers^[0][VK_CONTROL] := $80;
      if ssRight  in Shift then pKeyBuffers^[0][VK_RBUTTON] := $80;
      if ssLeft   in Shift then pKeyBuffers^[0][VK_LBUTTON] := $80;
      if ssMiddle in Shift then pKeyBuffers^[0][VK_MBUTTON] := $80;
      SetKeyboardState(pKeyBuffers^[0]);
      if ssAlt in Shift then
      begin
        PostMessage(hWindow, WM_SYSKEYDOWN, Key, lParam);
        PostMessage(hWindow, WM_SYSKEYUP, Key, lParam or $C0000000);
      end
      else
      begin
        PostMessage(hWindow, WM_KEYDOWN, Key, lParam);
        PostMessage(hWindow, WM_KEYUP, Key, lParam or $C0000000);
      end;
      Application.ProcessMessages;
      SetKeyboardState(pKeyBuffers^[1]);
    finally
      if pKeyBuffers <> nil then Dispose(pKeybuffers);
    end;
  end;
end;