包括imagegrabscreen php功能到按钮onclick而不刷新页面

Question

I'm trying to create a button with an onclick function that activates the imggrabscreen php function. Problem is, I've done several codes and so far the only function that I was able to use was a submit input type in which this refreshes the page. I tried using button as an input type but unfortunately, it does not save any screenshots upon clicking the button. Here's the code that I'm using so far.

if(isset($_POST['btnscreen']))
{

    $im = imagegrabscreen();
    imagepng($im, "screenshot.png");
}
ob_end_flush();
?>

<form method="post" action="" enctype="multipart/form-data"> 
    <br>
    <input type="submit" value="Click to Screenshot" id="btnscreen" name="btnscreen"></center>
    <br><br>
</form>

</div>

Answer 1

php is parsed and executed server side (pre-processing) so you cannot call any php functions after the page has been sent to the browser. The only way to do this is to make a new request to the server (ajax).

I can't quite grasp what your function does (php cannot make a screenshot of what your browser is displaying as it has no information of how it has been rendered - please note different browsers may display the page differently).

I would try reading up on html5 canvas element which can achieve that (e.g. https://html2canvas.hertzen.com/).

Hope this helps