Php – Delete all entrys if checkbox is checked

I have created a form that displays a list of database entries. There is a checkbox for each value. When I check the checkbox, I want to delete this entry.

My form class looks like this:

//Räume auslesen
        $rooms = $DB->get_records_sql( 
                'SELECT LBTB.id, LBTB.datum, LBTB.roomid, LBTB.ustd, 
                        LBTB.userid, RAUM.raumname, RAUM.raumnummer 
                FROM {bs_steinweg} LBTB
                    LEFT JOIN {bs_raume} RAUM ON LBTB.roomid = RAUM.id
                WHERE roomid > "0"
            ');

        foreach ($rooms as $room) {
            $newdate = date( 'd.m.Y', strtotime( $room->datum ) );
            $mform->addElement('html', '<tr><th scope="row">');
            $mform->addElement('advcheckbox', 'roomid[]','','','', $room->id);
            $mform->addElement('html', '</th><td>');
            $mform->addElement("html", "$room->raumname");
            $mform->addElement('html', '</td><td>');
            $mform->addElement("html", "$newdate");
            $mform->addElement('html', '</td><td>');
            $mform->addElement("html", "$room->ustd");
            $mform->addElement('html', '</td></tr>');
            $mform->addElement('hidden', 'id', $room->id);
            $mform->setType('id', PARAM_INT);
        }

I try to delete the data like this:

if ( !empty( $fromform->delete ) ) {
        if ( !empty( $fromform->roomid ) ) {
            foreach ( $fromform->roomid as $room_id ) {
                print_r($fromform->id);
                /* $DB->delete_records( 'bs_steinweg', [ 'id' => $room_id ] ); */
            }
            /* $getDeleteCanceld = get_string( 'getDeleteCanceld', 'local_buchungssystem' );
            redirect( $CFG->wwwroot . '/local/buchungssystem/meine_fach_buchungen_sw.php', $getDeleteCanceld ); */
        } else {
            // Handle the case where no rooms were selected.
            $getDeleteCanceld = get_string( 'noRoomsSelected', 'local_buchungssystem' );
            redirect( $CFG->wwwroot . '/local/buchungssystem/meine_fach_buchungen_sw.php', $getDeleteCanceld );
        }
    }

The output with print_r($room_id) does not give me any value.

The output with print_r($fromform->id) only gives me the last value. Even if I select the first value, it always gives me the last ID.

Counting the whole thing up with a for loop also doesn’t output any value. It doesn’t matter whether I output print_r($room_id) or print_r($fromform->id):

if ( !empty( $fromform->delete ) ) {
        if ( !empty( $fromform->roomid ) ) {
            foreach ( $fromform->roomid as $room_id ) {
                for ( $i = 0; $i <= $room_id; $i++ ) {
                print_r($room_id);
                }
                /* $DB->delete_records( 'bs_steinweg', [ 'id' => $room_id ] ); */
            }
            /* $getDeleteCanceld = get_string( 'getDeleteCanceld', 'local_buchungssystem' );
            redirect( $CFG->wwwroot . '/local/buchungssystem/meine_fach_buchungen_sw.php', $getDeleteCanceld ); */
        } else {
            // Handle the case where no rooms were selected.
            $getDeleteCanceld = get_string( 'noRoomsSelected', 'local_buchungssystem' );
            redirect( $CFG->wwwroot . '/local/buchungssystem/meine_fach_buchungen_sw.php', $getDeleteCanceld );
        }
    }

My solution:

$mform->addElement('advcheckbox', "laptopid[$laptop->id]",'','','', $laptop->id);

The processing:

if ( !empty( $fromform->delroomsw ) ) {
    if ( !empty( $fromform->roomid ) ) {
        $checked_values = $fromform->roomid;
        foreach ( $checked_values as $val ) {
            //Räume auslesen
            $rooms = $DB->get_record_sql( "SELECT * FROM {bs_steinweg} WHERE id = $val" );
            if ( $rooms->userid == $USER->id ) {
                $DB->delete_records( 'bs_steinweg', [ 'id' => $val ] );
            } else {
                $getDeleteCanceld = get_string( 'noDeleteRights', 'local_buchungssystem' );
                redirect( $CFG->wwwroot . '/local/buchungssystem/meine_buchungen.php', $getDeleteCanceld );
            }
        }
        $getDeleteCanceld = get_string( 'getDeleteCanceld', 'local_buchungssystem' );
        redirect( $CFG->wwwroot . '/local/buchungssystem/meine_buchungen.php', $getDeleteCanceld );
    }

}