<!DOCTYPE html>
<html>
<body>
<?php
// Variable to check
$int = 0;
if (filter_var($int, FILTER_VALIDATE_INT) === 0 || !filter_var($int, FILTER_VALIDATE_INT) === false) {
echo("Variable is an integer");
} else {
echo("Variable is not an integer");
}
?>
</body>
</html>