pass javascript variable to the php code

Question

I have one question.. I want to pass javascript variable to php script, on the same page as javascript is located... I have second code:

<script type="text/javascript">
    function getID(i)
    {
        var table = document.getElementById("tblPersons");
        var row = table.rows[i];    
        alert(row.id);

        //window.location.href = window.location+"?id="+row.id;

        $.ajax({
        type: 'POST',
        url: 'index.php',
        data: {'variable': row.id},
        });
    }
</script>

$selected_row = $_POST['variable'];
echo $selected_row;
                            }

but if I try to var_dump $_post['variable'], I got null in echo...

so can anyone help with my problem?

You have `$_POST['value']` and `$_POST['variable']`, which one is correect? — user229044, Aug 13 '13 at 11:57
emmm, no mater... I just deleted if statement and also got null in var_dump — vladimir, Aug 13 '13 at 12:00
Where exactly are you checking for the output? Are you expecting it to be there right in the same page underneath the script? — deceze, Aug 13 '13 at 12:04

score 0 · Answer 1 · edited May 23 '17 at 11:49

See Reference: Why does the PHP (or other server side) code in my Javascript not work?

The code is executed like this:

server executes any PHP (including your var_dump, which echoes nothing)
servers sends resulting HTML/Javascript code to browser
browser parses HTML and executes Javascript
Javascript sends AJAX request to server
server receives request and executes PHP code, this time outputting something
Javascript receives the response of the AJAX call (no visible output yet)
you do nothing with the received result

Watch the Network tab of your browser debugging tool of choice (Firebug for Firefox, Web Inspector for Chrome/Safari) to see what's really happening.

pass javascript variable to the php code

1 Answers1