- var_dump: documentation ( source)
- filter_var: documentation ( source)
<?php
var_dump([
filter_var('1', FILTER_VALIDATE_INT),
filter_var('1dfdsfsd', FILTER_VALIDATE_INT),
filter_var('1 zemlekop', FILTER_VALIDATE_INT),
filter_var('0,5', FILTER_VALIDATE_INT),
]);