How can PHP and JavaScript be integrated to open popup windows successfully in a PHP script?

To open popup windows successfully in a PHP script, you can use JavaScript within the PHP code to trigger the popup window. You can achieve this by echoing JavaScript code that opens the popup window when a certain condition is met in the PHP script.

<?php
// PHP code to determine when to open the popup window
$openPopup = true;

// Echo JavaScript code to open the popup window
if($openPopup) {
    echo '<script type="text/javascript">
            window.open("popup.html", "Popup", "width=400,height=400");
          </script>';
}
?>