filter_input_array

Note that although you can provide a default filter for the entire input array there is no way to provide a flag for that filter without building the entire definition array yourself.So here is a small function that can alleviate this hassle!<?phpfunction filter_input_array_with_default_flags($type, $filter, $flags, $add_empty = true) {    $loopThrough = array();    switch ($type) {        case INPUT_GET : $loopThrough = $_GET; break;        case INPUT_POST : $loopThrough = $_POST; break;        case INPUT_COOKIE : $loopThrough = $_COOKIE; break;        case INPUT_SERVER : $loopThrough = $_SERVER; break;        case INPUT_ENV : $loopThrough = $_ENV; break;    }       $args = array();    foreach ($loopThrough as $key=>$value) {        $args[$key] = array('filter'=>$filter, 'flags'=>$flags);    }        return filter_input_array($type, $args, $add_empty);}?>

[New Version]This function is very useful for filtering complicated array structure.Also, Some integer bitmasks and invalid UTF-8 sequence detection are available.Code:<?php/** * @param  integer $type    Constant like INPUT_XXX. * @param  array   $default Default structure of the specified super global var. *                          Following bitmasks are available: *  + FILTER_STRUCT_FORCE_ARRAY - Force 1 dimensional array. *  + FILTER_STRUCT_TRIM        - Trim by ASCII control chars. *  + FILTER_STRUCT_FULL_TRIM   - Trim by ASCII control chars, *                                full-width and no-break space. * @return array            The value of the filtered super global var. */define('FILTER_STRUCT_FORCE_ARRAY', 1);define('FILTER_STRUCT_TRIM', 2);define('FILTER_STRUCT_FULL_TRIM', 4);function filter_struct_utf8($type, array $default) {    static $func = __FUNCTION__;    static $trim = "[\\x0-\x20\x7f]";    static $ftrim = "[\\x0-\x20\x7f\xc2\xa0\xe3\x80\x80]";    static $recursive_static = false;    if (!$recursive = $recursive_static) {        $types = array(            INPUT_GET => $_GET,            INPUT_POST => $_POST,            INPUT_COOKIE => $_COOKIE,            INPUT_REQUEST => $_REQUEST,        );        if (!isset($types[(int)$type])) {            throw new LogicException('unknown super global var type');        }        $var = $types[(int)$type];        $recursive_static = true;    } else {        $var = $type;    }    $ret = array();    foreach ($default as $key => $value) {        if ($is_int = is_int($value)) {            if (!($value | (                FILTER_STRUCT_FORCE_ARRAY |                FILTER_STRUCT_FULL_TRIM |                 FILTER_STRUCT_TRIM            ))) {                $recursive_static = false;                throw new LogicException('unknown bitmask');            }            if ($value & FILTER_STRUCT_FORCE_ARRAY) {                $tmp = array();                if (isset($var[$key])) {                    foreach ((array)$var[$key] as $k => $v) {                        if (!preg_match('//u', $k)){                            continue;                        }                        $value &= FILTER_STRUCT_FULL_TRIM | FILTER_STRUCT_TRIM;                        $tmp += array($k => $value ? $value : '');                    }                }                $value = $tmp;            }        }        if ($isset = isset($var[$key]) and is_array($value)) {            $ret[$key] = $func($var[$key], $value);        } elseif (!$isset || is_array($var[$key])) {            $ret[$key] = null;        } elseif ($is_int && $value & FILTER_STRUCT_FULL_TRIM) {            $ret[$key] = preg_replace("/\A{$ftrim}++|{$ftrim}++\z/u", '', $var[$key]);        } elseif ($is_int && $value & FILTER_STRUCT_TRIM) {            $ret[$key] = preg_replace("/\A{$trim}++|{$trim}++\z/u", '', $var[$key]);        } else {            $ret[$key] = preg_replace('//u', '', $var[$key]);        }        if ($ret[$key] === null) {            $ret[$key] = $is_int ? '' : $value;        }    }    if (!$recursive) {        $recursive_static = false;    }    return $ret;}?>

This function is very useful for filtering complicated array structure.Code:<?phpfunction filter_request($var, $default_structure) {    $ret = array();    foreach ($default_structure as $key => $value) {        if (!isset($var[$key])) {            $ret[$key] = $value;        } elseif (is_array($value)) {            $ret[$key] = filter_request($var[$key], $value);        } elseif (is_array($var[$key])) {            $ret[$key] = $value;        } else {            $ret[$key] = $var[$key];        }    }    return $ret;}?>Sample Usage:<?php$_GET['a']['wrong_structure'] = 'foo';$_GET['b']['c'] = 'CORRECT';$_GET['b']['d']['wrong_structure'] = 'bar';$_GET['unneeded_item'] = 'baz';var_dump(filter_request($_GET, array(    'a' => 'DEFAULT',    'b' => array(        'c' => 'DEFAULT',        'd' => 'DEFAULT',    ),)));?>Sample Result:array(2) {  ["a"]=>  string(21) "DEFAULT"  ["b"]=>  array(2) {    ["c"]=>    string(12) "CORRECT"    ["d"]=>    string(21) "DEFAULT"  }}

Beware: if none of the arguments is set, this function returns NULL, not an array of NULL values./* No POST vars set in request$_POST = array();*/$args = array('some_post_var' => FILTER_VALIDATE_INT);$myinputs = filter_input_array(INPUT_POST, $args);var_dump($myinputs);Expected Output: array(1) { ["some_post_var"]=> NULL } Actual Output: NULL

Looks like filter_input_array isn't aware of changes to the input arrays that were made before calling filter_input_array. Instead, it always looks at the originally submitted input arrays.So this will not work:$_POST['my_float_field'] = str_replace(',','.',$_POST['my_float_field']);$args = array('my_float_field',FILTER_VALIDATE_FLOAT);$result = filter_input_array(INPUT_POST, $args);

[New Version]Example Usage:<?php$_GET['A']['a'] = '  CORRECT(including some spaces)    ';$_GET['A']['b'] = '  CORRECT(including some spaces)    ';$_GET['A']['c'] = "Invalid UTF-8 sequence: \xe3\xe3\xe3";$_GET['A']['d']['invalid_structure'] = 'INVALID';$_GET['B']['a'] = '  CORRECT(including some spaces)    ';$_GET['B']['b'] = "Invalid UTF-8 sequence: \xe3\xe3\xe3";$_GET['B']['c']['invalid_structure'] = 'INVALID';$_GET['B']["Invalid UTF-8 sequence: \xe3\xe3\xe3"] = 'INVALID';$_GET['C']['a'] = '  CORRECT(including some spaces)    ';$_GET['C']['b'] = "Invalid UTF-8 sequence: \xe3\xe3\xe3";$_GET['C']['c']['invalid_structure'] = 'INVALID';$_GET['C']["Invalid UTF-8 sequence: \xe3\xe3\xe3"] = 'INVALID';$_GET['unneeded_item'] = 'UNNEEDED';var_dump(filter_struct_utf8(INPUT_GET, array(    'A' => array(        'a' => '',        'b' => FILTER_STRUCT_TRIM,        'c' => '',        'd' => '',    ),    'B' => FILTER_STRUCT_FORCE_ARRAY,    'C' => FILTER_STRUCT_FORCE_ARRAY | FILTER_STRUCT_TRIM,)));?>Example Result:array(3) {  ["A"]=>  array(4) {    ["a"]=>    string(36) "  CORRECT(including some spaces)    "    ["b"]=>    string(30) "CORRECT(including some spaces)"    ["c"]=>    string(0) ""    ["d"]=>    string(0) ""  }  ["B"]=>  array(3) {    ["a"]=>    string(36) "  CORRECT(including some spaces)    "    ["b"]=>    string(0) ""    ["c"]=>    string(0) ""  }  ["C"]=>  array(3) {    ["a"]=>    string(30) "CORRECT(including some spaces)"    ["b"]=>    string(0) ""    ["c"]=>    string(0) ""  }}

While filtering input arrays, be careful of what flags you set besides FILTER_REQUIRE_ARRAY. For example, setting the flags like so:

<?php
$filter = array(
'myInputArr' => array('filter' => FILTER_SANITIZE_STRING,
                      'flags' => array('FILTER_FLAG_STRIP_LOW', 'FILTER_REQUIRE_ARRAY'))
);

$form_inputs = filter_input_array(INPUT_POST, $filter);
?>

.. will result in a blank $form_inputs['myInputArr'] regardless of what $_POST['myInputArr'] contains.

If you are trying to handling multiple form inputs with same name, then you must assign the `'flags'  => FILTER_REQUIRE_ARRAY` to the definitions entry.Example, you have a html form as such:<form> <input name="t1[]" value="Some string One" /> <input name="t1[]" value="Another String Two" /></form>Your definitions array will look a little like this:$args = array(  't1'    => array(      'name' => 't1',      'filter' => FILTER_SANITIZE_STRING,      'flags'  => FILTER_REQUIRE_ARRAY));

Here's an extended function that allows you to keep also the unfiltered items/args from the request, while you also apply validation to some of them:<?php$validationRules = [    'foo' => [        'filter' => FILTER_VALIDATE_REGEXP,        'options' => ['regexp' => '/^(bar|baz)$/i']    ]];$request = filter_input_array_keep_unfiltered_args(INPUT_POST, $validationRules);var_dump($request);function filter_input_array_keep_unfiltered_args($type, $filters, $addEmpty = true){    $rawRequest = filter_input_array($type);    $validationRules = [];    foreach ($rawRequest as $key => $value) {        $validationRules[$key] = isset($filters[$key]) ? $filters[$key] : ['filter' => FILTER_DEFAULT];    }    return filter_input_array($type, $validationRules, $addEmpty);}?>