fingerprintjs2到php变量

Question

I like to get fingerprint as php variable, I get the follow but do not want to work.

<p>fingerprint2: <strong id="fp2"></strong></p>

<script src="/fingerprintjs2/fingerprint2.js"></script>
<script>
    var fp2 = new Fingerprint2();
    fp2.get(function(result) {
        console.log(result);
        $("#fp2").text(result);
    });
</script>

$myphpvar = "<script>document.write(fp2.get());</script>"; 

echo $myphpvar;

Answer 1

The Javascript is run after the PHP has completed. Client side VS server side code. I have solved this in the past by running the PHP within a PHP file that renders an image. This method is often referred to pixel tracking.

Here are the basics, you need to pass your variables in Javascript to a PHP file that renders an image:

document.write("<img src=fingerprint.php?x="+x+"&y="+y+" width=1 height=1>");

In the above case it passed Javascript variables x and y to the PHP image.

Then the fingerprint.php script looks like:

    <?php
    header("Content-type: image/png");
    session_start();

    $x = $_REQUEST['x'];
    $y = $_REQUEST['y'];

    $_SESSION['x'] = $x;
    $_SESSION['y'] = $y              

    // SHOW THE IMAGE
    $im      = imagecreatefrompng("fingerprint.png");

    imagepng($im);
    imagedestroy($im);

    ?>

The png image can be anything you want as it will just be a 1 x 1 image on your final screen. You now have the Javascript variables in your PHP. As the code starts a session you could write the variables to a session and collect them later in another script, or write them to a database and recover later. Try with my simple example to ensure you have it working then expand from there.