If I have javascript something like this:
<javascript>
function myvalue()
{
var a = 3;
}
</javascript>
How can I get the value of the variable a from the function. So, I can perform operation inside php code, something like this:
<?php
$b = 1;
$c = $b + a (variabel a from the function);
echo $c; // return 3
?>
Thank you very much
You can do this in two ways.
Here is a way to do this via AJAX
Step 1 Get the jQuery library from here: https://ajax.googleapis.com/ajax/libs/jquery/1.8/jquery.min.js
Step 2 The html page:
<html>
<head></head>
<body>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.8/jquery.min.js"></script>
<script>
function myvalue() {
var a = 3;
$.ajax({
url: 'ajax_example.php'
cache: false,
type: 'GET',
data: {var: a},
dataType: 'JSON',
beforeSend: function() { alert("About to deploy ajax request");
success: function(response)
{
console.log(response);
if(response.success) {
alert(response.var);
} else {
alert(response.message);
}
}
});
$(document.ready(function() {
myvalue();
});
<script>
</body>
</html>
Step 3 The PHP page ajax_example.php
<?php
header("Cache-Control: no-cache, must-revalidate");
header("Expires: Sat, 26 Jul 1997 05:00:00 GMT");
header('Content-Type: application/json; charset=utf-8');
$var = isset($_GET['var']) ? $_GET['var'] : FALSE;
if($var)
{
$var = htmlspecialchars($var, ENT_QUOTES, 'UTF-8');
echo json_encode(array("success" => true, "var" => $var, "message" => "Example message"));
} else {
echo json_encode(array("success" => false, "message" => "You need to provide a value"));
}
You should send the JS variable value through AJAX call to the PHP page.
That's how the process works.
You have to use AJAX.
php runs in server, and javascript in cleint browser.
First code runs in server then it comes to browser so you can not pass js variables to php directly. you have to create a http request pass it to server using AJAX.
ref : http://api.jquery.com/jQuery.ajax/ for jquery ajax implementation.
