procedure TForm1.Button23Click(Sender: TObject);
VAR
    I : Integer;
begin
    FOR I := 0 TO Panel1.ControlCount - 1 DO
        IF Panel1.Controls[I].ClassNameIs('TDBEdit') then
           TDBEdit(Panel1.Controls[I]).DataSource := DataSource1;
end;

 
procedure TForm1.Button1Click(Sender: TObject);
var
  i:integer;
begin
  for i:=1 to 3 do
  TDBEdit(FindComponent('DBEdit'   IntToStr(i))).DataSource := DataSource1;
end;