Uncaught SyntaxError: Unexpected token < in JSON

[SVerheijen]

$.ajax({
                            type: "POST",
                            url: "aj/write.php",
                            dataType: "html",
                            data: update
                        }).done(function (returned) {
                            var data;
                            data = JSON.parse(returned);

                            message = data.message;


                            if (data.code == 200) {
                                lastChanged = data.users;
                                var params = {};
                                params.changes = lastChanged;
                                params.newTask = data.new;
                                if (data.new.projectleider == false) {
                                    params.organizer = {
                                        'naam': currentUser.naam,
                                        'email': currentUser.email
                                    };
                                } else {
                                    params.organizer = {
                                        'naam': data.new.projectleider.naam,
                                        'email': data.new.projectleider.email
                                    };
                                }

                                message = message + " <a href='#' onclick='outlookMail(" + JSON.stringify(params) + ", \"FREE\")'>Mail wijzigingen (Vrij)</a> <b>OF</b> <a href='#' onclick='outlookMail(" + JSON.stringify(params) + ", \"BUSY\")'>Mail wijzigingen (Bezet)</a> <b>OF</b> <a href='#' onclick='outlookMail({}, \"NONE\")'>Melding sluiten (geen mail)</a>";
                            } else if (data.code == 204) {
                                message = data.message;
                            }

                            $("#notifybar").html(message);
                            $("#notifybar").animate({'height': 'show'}, 400);

                        });

<?php
    include '../../includes/open_database_beheer.php';
    include '../resources/database/MysqliDb.php';
    $db = new MysqliDb ($server, $user, $password, $database);


    // OLD
    // $queryForCheckInLijst = "SELECT `gebruikersid`, `datum`, `dagdeel`, `legid` FROM `planning_lijst` WHERE `gebruikersid` = ( SELECT ID FROM planning_gebruikers WHERE login = ? LIMIT 1) AND `datum` = ? AND `dagdeel` = ?";
    // NEW
    $queryForCheckInLijst = "
        SELECT `gebruiker` gebruikersid, `datum`, `dagdeel`, `taak` legid
        FROM `planning`
        WHERE 
            `gebruiker` = ( SELECT `id` FROM `gebruikers` WHERE `login` = ? LIMIT 1) 
            AND `datum` = ? 
            AND `dagdeel` = ?
    ";

    $return = [];
    if (!empty($_POST)) {
        $return['postedIn'] = $_POST;
        $return['users'] = [];


        foreach ($_POST as $data) {
            if ($data['changeto'] == "griditem undefined") {
                $id = 0;
                $newName = "Standaardindeling";
                $projectLead = false;
            } else {
                $id = substr($data['changeto'], 14);

                $newName = $db->rawQueryValue("
                    SELECT
                        `naam`
                    FROM
                        `legenda`
                    WHERE
                        `id` = ?
                    limit 1
                ", array(






























                ))[0];

                $projectLead = $db->rawQueryOne("
                    SELECT
                        `legenda`.`projectleider`,
                        `gebruikers`.`naam`,
                        `gebruikers`.`email`
                    FROM
                        `legenda`
                    INNER JOIN `gebruikers`
                    ON `legenda`.`projectleider` = `gebruikers`.`id`
                    WHERE
                        `legenda`.`id` = ?
                ", array(
                    $id
                ));
            }
            if (!isset($return["new"])) {
                $return["new"] = [
                    "id" => $id,
                    "name" => $newName,
                    "projectleider" => ($projectLead == null ? false : $projectLead)
                ];
            }

            /* if ($data['daypart'] == "AM") { $daypart = 0; };
            if ($data['daypart'] == "PM") { $daypart = 1; };
            if ($data['daypart'] == "NIGHT") { $daypart = 2; }; */
//OLD       $daypart = (($data['daypart'] == "AM") ? 0 : 1);
//NEW $daypart word een (0 als AM oftewel ochtend, 1 als PM oftewel middag, 2 als NIGHT oftewel avond)
            switch ($data['daypart']) {
                case "AM":
                    $daypart = 0;
                    break;
                case "PM":
                    $daypart = 1;
                    break;
                case "NIGHT":
                    $daypart = 2;
                    break;
                default:
                    $daypart = 0;
                    break;
            }
            //var_dump ($daypart); die();
            $date = $data['date'];
            //echo '<h1>'.$date.'<h1>'; die();
            $CheckInLijstResult = $db->rawQueryOne($queryForCheckInLijst, array($data['uid'], $date, $daypart));

            if (!isset($return['users'][$data['uid']])) {
                $return['users'][$data['uid']] = [];
            }
            if (!isset($return['users'][$data['uid']]['changes'])) {
                $return['users'][$data['uid']]['changes'] = [];
            }
            if (!isset($return['users'][$data['uid']]['info'])) {
                $return['users'][$data['uid']]['info'] = [];
                $userdata = $db->rawQueryOne("
                    SELECT
                        `naam`,
                        `email`
                    FROM 
                        `gebruikers`
                    WHERE
                        `id` = ( SELECT `id` FROM `gebruikers` WHERE `login` = ? LIMIT 1) 
                ", array(
                    $data['uid']
                ));
                $return['users'][$data['uid']]['info'] = $userdata;
            }
            $temp = [];

            unset($exists);
            // Warning: This might be a security hole (unsafe query, vulnerable to injection). Unpatched because it's running on the internal network and includes only non-critical data.
            if (isset($data['changingDefault']) && $data['changingDefault'] == 1) {
				//OUD WERKT NIET VOOR NIGHT
                //$field = strtolower(preg_replace("/^(\w{2})([ab])(\w\w)$/", "$1_$2_$3", $data['date']));
                
				//NIEUW WERKT WEL VOOR NIGHT
				$array = array();
				$array = $data['date'];				
				$dag = $array[0].$array[1];
				$week = $array[2];
				$dag_deel = substr($data['date'],3);
				$field = $dag.'_'.$week.'_'.$dag_deel;
				$field = strtolower($field);
								
                //OLD
                //$query = "UPDATE planning_gebruikers SET $field = {$id} WHERE login = ?";
                //NEW
                $query = "UPDATE `gebruikers` SET $field = {$id} WHERE login = ?";
                $db->rawQuery($query, array($data['uid']));

            } else if (count($CheckInLijstResult) > 0) {
                $leaveLegendId = $db->rawQueryValue("SELECT `id` FROM `legenda` WHERE `naam` = 'VRIJ' LIMIT 1");

                //Als de nieuwe indeling gelijk is aan de standaardindeling van de gebruiker,verwijder de gevonden rij in planing_lijst.
                if ($id == 0) {
                    //OLD
                    //$queryDelete = "DELETE FROM `planning_lijst` WHERE `gebruikersid` = {$CheckInLijstResult["gebruikersid"]} AND `datum` = '{$CheckInLijstResult["datum"]}' AND `dagdeel` = {$CheckInLijstResult["dagdeel"]}";
                    //NEW
                    $queryDelete = "DELETE FROM `planning` WHERE `gebruiker` = ? AND `datum` = ? AND `dagdeel` = ?";
                    $db->rawQuery($queryDelete, array(
                        $CheckInLijstResult["gebruikersid"],
                        $CheckInLijstResult["datum"],
                        $CheckInLijstResult["dagdeel"]
                    ));
                } else {
                    //OLD
                    //$db->rawQuery("UPDATE `planning_lijst` SET `legid` = ? WHERE `gebruikersid` = (SELECT ID FROM planning_gebruikers WHERE login = ? LIMIT 1) AND `datum` = ? AND `dagdeel` = ?", array($id, $data['uid'], $date, $daypart));
                    //NEW

                    $db->rawQuery("
                    UPDATE `planning` SET `taak` = ? 
                    WHERE `gebruiker` = (SELECT `id` FROM `gebruikers` WHERE `login` = ? LIMIT 1) AND `datum` = ? AND `dagdeel` = ?
                  ", array($id, $data['uid'], $date, $daypart)
                    );
                }


                if ($data['changeFrom'] == "griditem item_" . $leaveLegendId . " selected") {
                    try {
                        $exists = $db->rawQueryValue("
                            SELECT `verlof_dagen`.`id`
                            FROM `verlof_dagen` 
                            INNER JOIN `verlof` ON `verlof_dagen`.`verlof` = `verlof`.`id` 
                            WHERE 
                                `verlof`.`gebruiker` = ? 
                                AND `verlof_dagen`.`datum` = ? 
                                AND `verlof_dagen`.`dagdeel` = ?
                            LIMIT 1
                        ", array(
                            $CheckInLijstResult["gebruikersid"],
                            $CheckInLijstResult["datum"],
                            $CheckInLijstResult["dagdeel"]
                        ));
                        if (isset($exists)) {
                            $db->rawQuery("
                                DELETE FROM `verlof_dagen`  
                                WHERE 
                                    `verlof_dagen`.`id` = ?
                            ", array(
                                $exists[0]
                            ));
                        }
                    } catch (Exception $ex) {
                        $return = [];
                        $return['code'] = 500;
                        $return['message'] = "Er is iets mis gegaan met het verwijderen in de tabel verlof_dagen";
                        echo json_encode($return);
                        return;
                    }
                }
            } else {
                if ($id == 0) {
                    //OLD
                    //$db->rawQuery("DELETE FROM planning_lijst WHERE gebruikersid=( SELECT ID FROM planning_gebruikers WHERE login =? LIMIT 1) AND datum=? AND dagdeel=?", array($data['uid'], $date, $daypart));
                    //NEW
                    $db->rawQuery("
                        DELETE FROM `planning` 
                        WHERE `gebruiker`=( SELECT `id` FROM `gebruikers` WHERE `login` = ? LIMIT 1) 
                        AND `datum` = ?
                        AND `dagdeel` = ?
                    ", array($data['uid'], $date, $daypart));
                } else {
                    $legid = substr($data['changeto'], 14);

                    //OLD
                    //$query = "INSERT INTO planning_lijst(gebruikersid, datum, dagdeel, legid) VALUES(( SELECT ID FROM planning_gebruikers WHERE login =? LIMIT 1), ?, ?, ?)";
                    //NEW
                    $query = "
                        INSERT INTO `planning`(
                            `gebruiker`, `datum`, `dagdeel`, `taak`
                        ) VALUES(
                            ( SELECT `id` FROM `gebruikers` WHERE `login` = ? LIMIT 1),
                            ?,
                            ?,
                            ?
                        )
                    ";
                    $db->rawQuery($query, array($data['uid'], $date, $daypart, $legid));
                }
            }

            $temp = array(

                "date" => $date,
                "daypart" => $daypart
            );

            array_push($return['users'][$data['uid']]['changes'], $temp);
            unset($temp);
        }

        $return['lastQuery'] = $db->getLastQuery();
        $return['code'] = 200;
        $return['message'] = "Planning bijgewerkt!";
    } else {
        $return['code'] = 204; // "Geen inhoud"
        $return['message'] = "Er is voor zo ver er gecontroleerd kan worden, niks meegestuurd. Probeer tenminste 1 blokje te selecteren en probeer het dan opnieuw <a href='#' onclick='outlookMail({}, \"NONE\")'>Klik hier om de melding sluiten</a>";
    }
    echo json_encode($return);

VM2851:1 Uncaught SyntaxError: Unexpected token < in JSON at position 0
    at JSON.parse (<anonymous>)
    at Object.<anonymous> (index.php?filter=0&w=10:236)
    at n (jquery.min.js:2)
    at Object.fireWith [as resolveWith] (jquery.min.js:2)
    at w (jquery.min.js:4)
    at XMLHttpRequest.d (jquery.min.js:4)

I don't know why there is an '<' in this error??? I can't find any place where it adds the '<'. Is this just my code or is this something else? Someone knows the solution???

[maxxd]

Typically this happens when PHP outputs an error. Check your console and see what the output is from the server. Looking at your $queryForCheckInLijst, it may be a SQL error - it looks like you've added a couple column names without commas. I haven't looked through the rest of the code, but that's a place to start.

[SVerheijen]

Typically this happens when PHP outputs an error. Check your console and see what the output is from the server. Looking at your $queryForCheckInLijst, it may be a SQL error - it looks like you've added a couple column names without commas. I haven't looked through the rest of the code, but that's a place to start.

Thanks for the answer. The query was right. I asked a friend and he found the problem. Somewhere in the query I forgot to put an variable. So it works fine now. Still thanks for helping !