Pass variable with jquery, open php page and pick it up - php

Question

I have two pages. On page one, called test1.html, I try to retreive the users timezone. I would like to send it of to a php page called test2.php and load that page instead of test1 with the variable (timezone). This is the code.
Test1.html:
<script type="text/javascript">
$(document).ready(function() {
var tz = jstz.determine(); // Determines the time zone of the browser client
var timezone = tz.name(); //'Asia/Kolhata' for Indian Time.
$.ajax({
type: 'POST',
url: 'test2.php',
data: {'timezone': timezone},
cache: false,
success: function(){
setTimeout(function () {
window.location = 'test2.php';
}, 3000);//this will redirct to somefile.php after 3 seconds
}
});
});
</script>
Test2.php
<?php
if(isset($_POST['timezone']))
{
$tz = $_POST['timezone'];
echo "Timezone is " .$tz;
}
else {
echo "Fail!";
}
?>
On pageload of test2.php, I only ever get the 'Fail!' message. The jquery and php part do work correct as I tested it with an alert call in test1.html to log the reponse from the php page. It gave the response I expected.
I think I lose my variable when the code is executed to reload test2.php in the same window. I just don't know how to bypass this problem. I want to use POST rather then GET if possible.
Any help greatly appreciated.
Little note: Idealy I want to use this javascript and the php to be on the same page but the 'problem' there is that php is of course executed serverside first and then it runs je js client side afterwards...

Answer 1

An alternative solution that still allows you to use POST, which you said you'd like, is to store the information in a session variable. The session is an object that can be used to store values between requests. See http://php.net/manual/en/book.session.php
Test1.html:
<script type="text/javascript">
$(document).ready(function() {
var tz = jstz.determine(); // Determines the time zone of the browser client
var timezone = tz.name(); //'Asia/Kolhata' for Indian Time.
$.ajax({
type: 'POST',
url: 'test2.php',
data: {'timezone': timezone},
cache: false,
success: function(){
setTimeout(function () {
window.location = 'test3.php';
}, 3000); }
});
});
</script>
Test2.php
<?php
// Start your session (if not already started)
if (session_status() == PHP_SESSION_NONE) {
session_start();
}
// Store posted timezone in the session, which will be available in future calls
if(isset($_POST['timezone'])) {
$_SESSION['timezone'] = $_POST['timezone'];
}
else {
echo "Fail!";
}
?>
Test3.php
<?php
// Start your session (if not already started)
if (session_status() == PHP_SESSION_NONE) {
session_start();
}
if(isset($_SESSION['timezone']) {
echo "Your timezone is " . $_SESSION['timezone'];
} else {
echo "Fail!";
}

Answer 2

You are misunderstanding the flow of how your client and server are interacting with each other. Your code sends a POST request to test2.php, and THEN (in the success callback that triggers when your request is done) it redirects to test2.php. The first time test2.php is run, it gets the timezone POST variable, but the second time it doesn't. You can see this by looking at network traffic in your browser's developer tools - you'll see two requests to test2.php. The first will return "Timezone is...", and the second (which your browser is showing) says "Fail!"
There are different ways to get what you want, but the easiest would be to skip the AJAX altogether and just send the timezone along with the redirect:
$(document).ready(function() {
var tz = jstz.determine(); // Determines the time zone of the browser client
var timezone = tz.name(); //'Asia/Kolhata' for Indian Time.
// This redirects to test2.php while setting a GET parameter called "timezone"
window.location = 'test2.php?timezone='+encodeURIComponent(timezone);
});
<?php
if(isset($_GET['timezone']))
{
$tz = $_GET['timezone'];
echo "Timezone is " .$tz;
}
else {
echo "Fail!";
}
?>