TMemo

Code:

procedure TForm1.Button1Click(Sender: TObject);

begin

if OpenDialog1.Execute then

   Memo1.Lines.LoadFromFile(OpenDialog1.FileName);

end;

procedure TForm1.Button2Click(Sender: TObject);

var

find: string;

text: string;

st, len: integer;

res: integer;

begin

if Memo1.SelStart >= Length(Memo1.Text) then

   Memo1.SelStart := 0;

st := Memo1.SelStart + 1;

if (Memo1.SelLength <= 0) or (not CheckBox1.Checked) then

begin

   inc(st, Memo1.SelLength);

   len := Length(Memo1.Text) - st;

end

else

   len := Memo1.SelLength;

text := copy(Memo1.Text, st, len);

find := Edit1.Text;

res := pos(find, text);

if res = 0 then

begin

   ShowMessage('Search string "' + find + '" not found');

   Exit;

end;

Memo1.SelStart := res + st - 2;

Memo1.SelLength := length(find);

end;