Parameters

variable

Value to filter.

filter

ID of a filter to use (see the Types of filters manual page).

options

Associative array of options or bitwise disjunction of flags. If filter accepts options, flags can be provided in "flags" field of array. For the "callback" filter, callback type should be passed. The callback must accept one argument, the value to be filtered, and return the value after filtering/sanitizing it.

<?php
// for filters that accept options, use this format
$options = array(
    'options' => array(
        'default' => 3, // value to return if the filter fails
        // other options here
        'min_range' => 0
    ),
    'flags' => FILTER_FLAG_ALLOW_OCTAL,
);
$var = filter_var('0755', FILTER_VALIDATE_INT, $options);

// for filter that only accept flags, you can pass them directly
$var = filter_var('oops', FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE);

// for filter that only accept flags, you can also pass as an array
$var = filter_var('oops', FILTER_VALIDATE_BOOLEAN,
                  array('flags' => FILTER_NULL_ON_FAILURE));

// callback filter
function foo($value)
{
    $ret = new stdClass;
    $ret->value = filter_var($value, FILTER_VALIDATE_BOOLEAN,
                             array('flags' => FILTER_NULL_ON_FAILURE));
    return $ret;
}
$var = filter_var('yes', FILTER_CALLBACK, array('options' => 'foo'));
?>