use javascript variable in php in jquery function

Question

I want to use javascript variable in php function.. my code is as below

$(document).ready(function() { 
 $("#btn_url").on('click', function() {
 var video_val = $("#video_url").val(); alert(video_val);
 alert('<?php echo getYoutubeDurationV3("<script>document.write(video_val);</script>"); ?>');
 });
 }); 

I want to use video_val variable in php function.. how can i do that ?

• mitkosoft: yes, you can pass it by using AJAX to any .php script.
• David: You're mixing client-side and server-side code in very strange ways. JavaScript and PHP have no knowledge of each other in this context, they run at completely different times on completely different hosts. You don't "use a JavaScript variable in PHP", instead of "make an AJAX request". That request includes the data you want to sent to the PHP application. That application can then use that data, perform some operation, and respond to the AJAX request. The client-side code then handles that response.
• epascarello: Do you understand the page lifecycle and how PHP and JavaScript interact? By the time the JavaScript code has run it is way to late to run PHP.
• ak_: If you're using PHP to list the videos on the page, the youtube API already has access to contentDetails.duration. You can echo that anywhere you need the video length.

Answer 1

You can use Ajax for this solution. When you place your PHP getYoutubeDurationV3 function in a .php file.

$(document).ready(function() { 
$("#btn_url").on('click', function() {
 var video_val = $("#video_url").val(); alert(video_val);
 $.ajax({
 url: 'yourphpscript.php',
 data: {duration: video_val},
 type: 'POST',
 success: function(data) {
 alert(data);
 }
 });
});
}); 

And in your PHP file you can get the value like this:

<?php
$duration = $_POST['video_val'];
//rest of your logic, in your case your function
//return your response back to your webpage.
return $response;
?>

Answer 2

yes, u can do that by ajax post method..

$(document).ready(function() { 
$("#btn_url").on('click', function() {
 var video_val = $("#video_url").val(); alert(video_val);
 $.ajax({
 url: 'ajax_file.php',
 data: {duration: video_val},
 type: 'POST',
 success: function(data) {
 alert(data);
 }
 });
});
}); 

And in ajax_file.php write below code..

<?php
$duration = $_POST['video_val'];
return $duration ;
?>