function HasProperty(Obj : TObject; Prop : string) : PPropInfo;
begin
    Result := GetPropInfo(Obj.ClassInfo, Prop);
end;

procedure TForm1.Button1Click(Sender: TObject);
var
    p : pointer;
begin
    p :=  HasProperty(Button1, 'Color');
    if p <> nil then
        SetOrdProp(Button1, p, clRed)
    else
        ShowMessage('Button has no color property');
    p :=  HasProperty(Label1, 'Color');
    if p <> nil then
        SetOrdProp(Label1, p, clRed)
    else
        ShowMessage('Label has no color property');
    p :=  HasProperty(Label1.Font, 'Color');
    if p <> nil then
        SetOrdProp(Label1.Font.Color, p, clBlue)
    else
        ShowMessage('Label.Font has no color property');
end;