[Janom]

Код:

procedure TForm1.Button1Click(Sender: TObject);
var
  sr: TSearchRec;
  i:integer;
  sDir:array of array [0..1] of Cardinal;
begin
RichEdit1.Clear;
 if (FindFirst(ExtractFilePath(ParamStr(0))+'\*.*', faAnyFile, sr) = 0) then
  begin
  repeat
  RichEdit1.Text:=RichEdit1.Text+sr.Name+' ';
  if sr.Attr and faDirectory <> 0 then //если папка то делаем её жирной
    begin
      SetLength(sDir,Length(sDir)+1);
      sDir[Length(sDir)-1,0]:=length(sr.Name);
      sDir[Length(sDir)-1,1]:=length(RichEdit1.Text)-length(sr.Name)-1;
    end;

  until FindNext(sr) <> 0;
  for i:=0 to Length(sDir)-1 do
    begin
      RichEdit1.SelStart:=sDir[i,1];
      RichEdit1.SelLength:=sDir[i,0];
      RichEdit1.SelAttributes.Style := [fsBold];
    end;
  FindClose(sr);
  sDir:=nil;
 end;
end;