How to get int instead string from form?

Question

Getting variable from form:

<form method = 'POST' action = ''>
        <input type = 'text' name = 'a' size = '1' >
        <input type = 'submit' value = 'Find it'>
</form>"

If I enter 1 and use gettype($POST_['a']) it returns me string, is it possible to enter int? because after this I want check if that variable is int.

UPDATE

Got answers that it returns always string and they offered me to use (int) or intval(), but then if it's really string like 'a' it returns 0, but it may be also integer value 0, how to overcome this problem?

UPDATE

After editing typo Brad Christie suggested best way, using is_numeric

Answer 1

// convert the $_POST['a'] to integer if it's valid, or default to 0
$int = (is_numeric($_POST['a']) ? (int)$_POST['a'] : 0);

You can use is_numeric to check, and php allows casting to integer type, too.

For actual comparisons, you can perform is_int.

Update

Version 5.2 has filter_input which may be a bit more robust for this data type (and others):

$int = filter_input(INPUT_POST, 'a', FILTER_VALIDATE_INT);

I chose FILTER_VALIDATE_INT, but there is also FILTER_SANITIZE_NUMBER_INT and a lot more--it just depends what you want to do.