如何将$ _SESSION变量添加到Ajax请求中并将数据插入到mysql数据库PHP中？

Question

I'm just beginning in web development and I am trying some stuff in PHP with Ajax. I recently downloaded a script which uses php,jquery and ajax. What it does is that it shows a calendar which enables input once a user clicks a particular day and add the data to the database once the user clicks the 'Add' button.

It looks somethings like this

Afterwards, I modified the database table wherein I added a user_id as a column because I wanted the calendar daily report to be viewed only by the user who adds data into it. Now, my problem is that I cannot use my $_SESSION['userSession'] into the Ajax request. I tried to add the variable into the mysqli queries but unfortunately, it produces this kind of error:

Notice: Undefined variable: u_id in C:\xampp\htdocseports\functions.php on line 288

I have two PHP files, One for the main page and the other one for processing the calendar and other functions for the calendar.

Here is what my reports.php file looks like:

 <?php
session_start();
include_once 'dbconnect.php';
include_once('functions.php');

if (!isset($_SESSION['userSession'])) {
    header("Location: index.php");
}

$query = $DBcon->query("SELECT * FROM users WHERE user_id=".$_SESSION['userSession']);
$userRow=$query->fetch_array();
$DBcon->close();

$u_id = $_SESSION['userSession']; //this  is the variable that I am trying to pass to the functions.php file

    ?>
<!-- The echo below produces the calendar view -->
<div id="calendar_div">
    <?php echo getCalender(); ?>
</div>

Now here is the sample of functions.php:

<?php


if(isset($_POST['func']) && !empty($_POST['func'])){
    switch($_POST['func']){
        case 'getCalender':
            getCalender($_POST['year'],$_POST['month']);
            break;
        case 'getEvents':
            getEvents($_POST['date']);
            break;
        //For Add Event
        case 'addEvent':
            addEvent($_POST['date'],$_POST['title'],$_POST['week'],$_POST['hours']);
            break;
        default:
            break;
    }
}

?>



<script type="text/javascript">
    function getCalendar(target_div,year,month){
        $.ajax({
            type:'POST',
            url:'functions.php',
            data:'func=getCalender&year='+year+'&month='+month,
            success:function(html){
                $('#'+target_div).html(html);
            }
        });
    }

    function getEvents(date){
        $.ajax({
            type:'POST',
            url:'functions.php',
            data:'func=getEvents&date='+date,
            success:function(html){
                $('#event_list').html(html);
                $('#event_add').slideUp('slow');
                $('#event_list').slideDown('slow');
            }
        });
    }
    //For Add Event
    function addEvent(date){

        $('#eventDate').val(date);
        $('#eventDateView').html(date);
        $('#event_list').slideUp('slow');
        $('#event_add').slideDown('slow');
    }
    //For Add Event
    $(document).ready(function(){
        $('#addEventBtn').on('click',function(){
            var date = $('#eventDate').val();
            var title = $('#eventTitle').val();
            var week = $('#eventWeek').val();
            var hours = $('#eventHours').val();
            $.ajax({
                type:'POST',
                url:'functions.php',
                data:'func=addEvent&date='+date+'&title='+title+'&week='+week+'&hours='+hours,
                success:function(msg){
                    if(msg == 'ok'){
                        var dateSplit = date.split("-");
                        $('#eventTitle').val('');
                        $('#eventWeek').val('');
                        $('#eventHours').val('');
                        alert('Daily report has been added.');
                        getCalendar('calendar_div',dateSplit[0],dateSplit[1]);
                    }else{
                        alert('Some problem occurred, please try again.');
                    }
                }
            });
        });
    });

function getEvents($date = ''){
    //Include db configuration file
    include 'dbconnect.php';
    $eventListHTML = '';
    $date = $date?$date:date("Y-m-d");
    //Get events based on the current date
    $result = $DBcon->query("SELECT title,hours FROM ojt_student_report WHERE date = '".$date."' AND status = 1 and user_id = '"$u_id"'");

    if($result->num_rows > 0){

        $eventListHTML = '<h2>Daily Report on '.date("l, d M Y",strtotime($date)).'</h2>';
        $eventListHTML .= '<ul class="list-group">';
        while($row = $result->fetch_assoc()){ 
            $eventListHTML .= '<li class="list-group-item"> <b>Daily Report:  </b><br>'.nl2br($row['title']). '<br>  <b>Working Hours: </b>' .$row['hours']. '</li>';
        }
        $eventListHTML .= '</ul>';

    }
    echo $eventListHTML;
}

/*
 * Add event to date
 */
function addEvent($date,$title,$week,$hours){
    //Include db configuration file
    include 'dbconnect.php';
    $currentDate = date("Y-m-d H:i:s");
    //Insert the event data into database 
    $insert = $DBcon->query("INSERT INTO ojt_student_report (title,date,week,hours,created,modified,user_id) VALUES ('".$title."','".$date."','".$week."','".$hours."','".$currentDate."','".$currentDate."','"$u_id"')");
    if($insert){
        echo 'ok';
    }else{
        echo 'err';
    }
}
?>

Basically, what I just wanted to do is to have different calendar and daily reports view for each user using the $_SESSION variable. I hope I was able to state my problem properly, any help will be appreciated. Thank you very much!

Answer 1

Try something like below code:

function getCalendar(target_div,year,month){
        $.ajax({
            type:'POST',
            url:'functions.php',
            data:'func=getCalender&year='+year+'&month='+month + '&uid=<?php echo $u_id ; ?>',
            success:function(html){
                $('#'+target_div).html(html);
            }
        });
    }