AdvancedCheckBoxList checkboxes = new AdvancedCheckBoxList();
foreach (System.Data.DataRowView fila in this.SqlDataSource3.Select(DataSourceSelectArguments.Empty)) {
	ListItem item = new ListItem();
	item.Value = fila["id_marca"].ToString();
	item.Text = "img:imagenes/" + fila["marca"].ToString() + ".gif";
	//example complete: "text:" & fila("marca").ToString() & ";img:imagenes/" & fila("marca").ToString() & ".gif"
	checkboxes.Items.Add(item);
}
checkboxes.RepeatColumns = 11;
checkboxes.RepeatDirection = RepeatDirection.Horizontal;
Controls.Add(checkboxes);