Drop tekst i TMemo

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm1 = class(TForm)
    Memo1: TMemo;
    procedure FormCreate(Sender: TObject);
  private
  procedure acceptFiles(var msg:tMessage);message WM_DROPFILES;
  public
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

uses
shellApi;

procedure TForm1.acceptFiles(var msg:tMessage);
var i,aCount:integer;
    aItem:array [0..255] of char;
    aExt,aFilter:string;
begin
memo1.clear;
aCount:=dragQueryFile(msg.wParam,$FFFFFFFF,aItem,255);
for i:=0 to aCount-1 do begin
  dragQueryFile(msg.wParam,i,aItem,255);
  memo1.lines.add(aItem)
end;
dragFinish(msg.wParam)
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
dragAcceptFiles(handle,true);
end;

end.

procedure TForm1.Memo1DragDrop(Sender, Source: TObject; X, Y: Integer);
var i:integer;aMemo:tMemo;
begin aMemo:=tMemo(sender);
if source is tMemo then aMemo.text:=aMemo.text+tMemo(source).selText+vbcrlf else
if source is tRichEdit then aMemo.text:=aMemo.text+tRichEdit(source).selText+vbcrlf else
if source is tListBox then with tListBox(source) do
  for i:=0 to items.count-1 do if selected[i] then aMemo.text:=aMemo.text+items[i]+vbcrlf else

aMemo.text:='Unsupported sender: '+sender.className
end;

with richEdit1.lines do text:=text;

procedure TForm1.RichEdit1Change(Sender: TObject);
begin
with richEdit1 do if lines.text<>text then lines.text:=trim(text)
end;

function forcePlainText(aRichEdit:tRichEdit):string;
var aStrm:tStringStream;s:string;aTag:integer;
begin if aRichEdit.tag=99 then exit;
aStrm:=tStringStream.create('');
with aRichEdit do begin plainText:=true;aTag:=tag;tag:=99;
  lines.saveToStream(aStrm);clear;
  result:=aStrm.dataString;lines.text:=result;tag:=aTag
end;aStrm.free
end;

procedure TForm1.RichEdit1Change(Sender: TObject);
begin
forcePlainText(richEdit1)
end;