I am trying to set a session variable’s value from within a class function, and comparing that session value at some later time inside a different function of the same class. None of these functions are in the __construct() function.
The problem seems to be that the comparison never returns true.
<?php
session_start();
$class = new Class();
?>
blah blah blah
<script type="text/javascript">
// Ajax function to call PHP that creates new Class isntance and executes a Class->function();
setInterval('checkNew()', 10000);
</script>
blah blah blah
// Another Ajax Function that calls creates a new Class isntance and executes the initial Class->function();
<body onload="getMessages();">
blah blah blah
This next function excerpt is ran from the script that the <body onload=""> ajax calls.
This is to compare this $_SESSION['last_sms'] later in a different function.
// Check the now() stamp of the most recent message loaded
$recent_msg_query = "SELECT date_received FROM messages ORDER BY date_received DESC LIMIT 1";
$recent_statement = $this->db_handle->prepare($recent_msg_query);
$recent_statement->execute();
$most_recent = $recent_statement->fetch(PDO::FETCH_NUM);
$_SESSION['last_sms'] = $most_recent[0];
This is the function inside the Class that is supposed to be doing the comparison, every ten seconds (via setInterval('checkNew()', 10000);)
public function checkNew()
{
// Check the now() stamp of the most recent message loaded and compares it
// to a stored now() stamp.
$recent_msg_query = "SELECT date_received FROM messages ORDER BY date_received DESC LIMIT 1";
$recent_statement = $this->db_handle->prepare($recent_msg_query);
$recent_statement->execute();
$most_recent = $recent_statement->fetch(PDO::FETCH_NUM);
if (!isset($_SESSION['last_sms'])) {
$_SESSION['last_sms'] = $most_recent[0];
}
if ($_SESSION['last_sms'] !== $most_recent[0]) {
echo "New message(s) available, refresh.";
} else {
echo "No new messages yet.";
}
}
When I send a new message, the page still says “No new messages yet.” Can you guys help me figure out where I’ve gone off the path here? This $_SESSION stuff is the only thing not working so far.
session_start()does not merely function as a session initiator. It must be called on every script which attempts to read or write to$_SESSION. Since your AJAX handler scripts are detached from the main PHP script that produced the page they are called from, and they function as entirely independent PHP scripts, you must also callsession_start()on the AJAX handling PHP script.