Share this page Tweet Follow us Related products Ultimate Pack  hot! iGrid Plotter  new! Image Editor Runtime Fusion Form Designer Object Inspector Print Suite Pro Commented Image Delphi Toys WinDowse Delphi Bonus TMS Scripter Studio Form Designer VB Form Designer .NET Print Suite .NET Gradient Controls .NET  new! Related links Win32.hlp online version MegaDetailed.NET Delphi to C# Special Free Software Promotion Offers for Resellers Hobby projects cdtrrracks.com books.storrre.com in3steps.com sovietphillumeny.com

You may use Perform method with EM_UNDO message for undo operation, and you can use EM_CANUNDO message to determine whether an edit operation can be undone.

procedure TForm1.Button1Click(Sender: TObject);
begin
  Edit1.Perform(EM_UNDO, 0, 0);
end;

procedure TForm1.Edit1Change(Sender: TObject);
begin
  if Edit1.Perform(EM_CANUNDO, 0, 0)<>0 then
    Button1.Enabled:=True;
end;

For more

Win32 programmer's reference

Download source