Как перетаскивать выделенный текст между компонентами Memo

Code:

type

TMyMemo = class(TMemo)

private

   FLastSelStart : Integer;

   FLastSelLength : Integer;

   procedure WMLButtonDown(var message: TWMLButtonDown); message WM_LBUTTONDOWN;

published

   property LastSelStart : Integer read FLastSelStart write FLastSelStart;

   property LastSelLength : Integer read FLastSelLength write FLastSelLength;

end;

Code:

procedure TMyMemo.WMLButtonDown(var message: TWMLButtonDown);

var

Ch: Integer;

begin

if SelLength > 0 then

begin

   Ch := LoWord(Perform(EM_CHARFROMPOS, 0,

   MakeLParam(message.XPos, message.YPos)));

   LastSelStart := SelStart;

   LastSelLength := SelLength;

   if (Ch >= SelStart) and (Ch <= SelStart+SelLength-1) then

     BeginDrag(True)

   else

     inherited;

end

else

   inherited;

end;

Code:

procedure TForm1.MyMemo1DragOver(Sender, Source: TObject; X, Y: Integer;

State: TDragState; var Accept: Boolean);

begin

Accept := Source is TMyMemo;

end;

Code:

procedure TForm1.MyMemo1DragDrop(Sender, Source: TObject;

X, Y: Integer);

var

Dst, Src : TMyMemo;

Ch : Integer;

Temp : string;

begin

Dst := Sender as TMyMemo;

Src := Source as TMyMemo;

Ch := LoWord(Dst.Perform(EM_CHARFROMPOS,0,MakeLParam(X,Y)));

if (Src = Dst) and (Ch >= Src.LastSelStart) and

(Ch <= Src.LastSelStart+Src.LastSelLength-1) then

   Exit;

Dst.Text := Copy(Dst.Text,1,Ch)+Src.SelText+

Copy(Dst.Text,Ch+1,Length(Dst.Text)-Ch);

Temp := Src.Text;

Delete(Temp,Src.LastSelStart+1,Src.LastSelLength);

Src.Text := Temp;

end;