<html>
<body>
// Variable to check
$url = "https://www.w3schools.com";
// Validate url
if (!filter_var($url, FILTER_VALIDATE_URL, FILTER_FLAG_QUERY_REQUIRED) === false) {
echo("$url is a valid URL with a query string");
} else {
echo("$url is not a valid URL with a query string");
}
</body>
</html>