procedure TQueryForm.Button1Click(Sender: TObject);
Var
    I,J : integer;
begin
    J := 0;
    for I := 0 to DataModules.ComponentCount - 1 do
        begin
            if DataModules.Components[i].ClassNameIs('TClientDataSet') then
                Inc(J);
        end;
    ShowMessage('There are '   IntToStr(J)   ' ClientDataSet(s) in '   DataModules.Name   ' !!');
end;