Szövegcsere TMemo tartalmában

	
procedure TForm1.Button1Click(Sender: TObject);
var
  i, p: integer;
  s: string;
begin
  for i:=0 to Memo1.Lines.Count -1 do begin
    s:=Memo1.Lines[i];
    repeat
      p:=Pos(Edit1.Text, s);
      if p>0 then begin
        Delete(s, p, Length(Edit1.Text));
        Insert(Edit2.Text, s, p);
        Memo1.Lines[i]:=s;
      end;
    until p=0;
  end; 
end;