Function Handling

Last updated: Fri, 30 Oct 2009

filter_var

(PHP 5 >= 5.2.0)

filter_var — Filtern einer Variablen durch einen spezifischen Filter

Beschreibung

mixed filter_var ( mixed $variable [, int $filter [, mixed $options ]] )

Parameter-Liste

variable: Wert der gefiltert werden soll. Arrays werden rekursiv gefiltert.
filter: ID des zu benutztenden Filters. Standard ist FILTER_SANITIZE_STRING.
options: Assoziatives Array mit Optionen oder bitweise Disjunktion von Flags. Wenn der Filter Optionen akzeptiert, können Flags auch im "flags" Feld des Arrays angegeben werden. Für "callback" Filter sollte der callback-Typ angegeben werden.

Rückgabewerte

Gibt die gefilterten Daten zurück oder FALSE wenn fehlgeschlagen.

Beispiele

Beispiel #1 filter_var()-Beispiel


<?php
var_dump(filter_var('bob@example.com', FILTER_VALIDATE_EMAIL));
var_dump(filter_var('example.com', FILTER_VALIDATE_URL, FILTER_FLAG_SCHEME_REQUIRED));
?>

Das oben gezeigte Beispiel erzeugt folgende Ausgabe:

string(15) "bob@example.com"
bool(false)

Siehe auch

filter_var_array() - Nimmt mehrere Variablen entgegen und filtert sie optional
filter_input() - Nimmt Variable von Außen entgegen und filtert sie optional
filter_input_array() - Nimmt mehrere Variablen von Außen entgegen und filtert sie optional
Informationen über den Callback-Typ

Function Handling

filter_var_array

Last updated: Fri, 30 Oct 2009

add a note User Contributed Notes
filter_var

drtebi at yahoo
25-Nov-2009 07:55


Notice that filter_var with FILTER_VALIDATE_EMAIL does not work if you are trying to get a String from an XML document e.g. via xpath. 



I often use XML files as configuration files and use a function that returns a string from the config file via xpath. While this worked fine before 5.2.11, it doesn't anymore (and shouldn't, since it's an XML Element, not a String). 



To overcome this problem, $variable can be type-casted:



<?php

$variable = fancyXmlGetFunction('from');

filter_var((String) $variable, FILTER_VALIDATE_EMAIL);

?>

madhamster
19-Aug-2009 05:42


Flags and options manual: http://www.w3schools.com/PHP/php_ref_filter.asp

suit dot 2009 at rebell dot at
07-Aug-2009 10:11


If PHP >= 5.2 is not present, you can use the regular expression of the original PHP-c-file:





http://svn.php.net/viewvc/php/php-src/trunk/ext/filter/logical_filters.c





Instead of:


<?php filter_var('bob@example.com', FILTER_VALIDATE_EMAIL)); ?>





Just use preg_match(); with a copy of the original regular expression (found in the void "php_filter_validate_email") in logical_filters.c





in fact, this expression (and the original filter-funktion) ignores RFC 5321 (Section 4.5.3.1. Size Limits and Minimums).

tedivm at tedivm dot com
22-Jun-2009 08:28


How to pass options and flags-





<?php


$options = array();


$options['options']['min_range'] = 1;


$options['options']['max_range'] = 10;


$options['flags'] = FILTER_FLAG_ALLOW_OCTAL;


filter_var(3, FILTER_VALIDATE_INT, $options);


?>

Meska
30-Apr-2009 07:08


Just a little filter to validate IP v4 & v6

This little script display result in function of the query

<?php

$ipv6="2a01:e35:aaa4:6860:a5e7:5ba9:965e:cc93";

$ipv4="82.237.3.3";

$fake = "3342423423";

$ipv4priv = "255.255.255.255";

$ipv6priv = "::1";

echo "<pre>";

echo $ipv4;

echo "<br />";

var_dump(filter_var($ipv4,FILTER_VALIDATE_IP));

echo "<br />";

echo $ipv6;

echo "<br />";

var_dump(filter_var($ipv6,FILTER_VALIDATE_IP));

echo "<br />";

echo $fake;

echo "<br />";

var_dump(filter_var($fake,FILTER_VALIDATE_IP));

echo "<br />";

echo $ipv4priv;

echo "<br/>";

echo "FILTER_VALIDATE_IP, FILTER_FLAG_NO_RES_RANGE";

echo "<br />";

var_dump(filter_var($ipv4priv,FILTER_VALIDATE_IP, FILTER_FLAG_NO_RES_RANGE));

echo "<br />";

echo $ipv4priv;

echo "<br/>";

echo "FILTER_FLAG_NO_PRIV_RANGE";

echo "<br />";

var_dump(filter_var($ipv4priv,FILTER_FLAG_NO_PRIV_RANGE));

echo "<br />";

echo $ipv6priv;

echo "<br/>";

echo "FILTER_FLAG_NO_PRIV_RANGE";

echo "<br />";

var_dump(filter_var($ipv6priv,FILTER_FLAG_NO_PRIV_RANGE));

echo "<br />";

echo $ipv6priv;

echo "<br />";

var_dump(filter_var($ipv6priv,FILTER_VALIDATE_IP));



echo "</pre>";



?>

jon dot bertsch at ucop dot edu
24-Mar-2009 03:49


Here's an actual example of the filter syntax with a flag since there doesn't appear to be a one liner for this anywhere:



'hours' => array('filter'=>FILTER_SANITIZE_NUMBER_FLOAT, 'flags' => FILTER_FLAG_ALLOW_FRACTION, 'options'=> '.')

dyer85 at gmail dot com
03-Nov-2008 10:00


Note that when using FILTER_VALIDATE_INT along with the FILTER_FLAG_ALLOW_HEX flag, the string "2f", for example, is not validated successfully, because you must use the "0x" prefix, otherwise, it treats the data as base 10.



The range options are also smart enough to recognize when the boundaries are exceeded in different bases.



Here's an example:



<?php



$foo = '256';

$bar = '0x100';

var_dump(validate_int($foo)); // false, too large

var_dump(validate_int($bar)); // false, too large



function validate_int($input)

{

  return filter_var(

    $input,

    FILTER_VALIDATE_INT,



    // We must pass an associative array

    // to include the range check options.

    array(

      'flags'   => FILTER_FLAG_ALLOW_HEX,

      'options' => array('min_range' => 1, 'max_range' => 0xff)

    )

  );

}



?>

visseraj at gmail dot com
28-Aug-2008 05:31


Here are the other possible flags that you can use:

http://us3.php.net/manual/hu/ref.filter.php

dale dot liszka at gmail dot com
09-Jul-2008 05:15


Here is how to use multiple flags (for those who learn better by example, like me):



<?php

echo "|asdf".chr(9).chr(128)."_123|";

echo "\n";

// "bitwise conjunction" means logic OR / bitwise |

echo filter_var("|asdf".chr(9).chr(128)."_123\n|" ,FILTER_SANITIZE_STRING, FILTER_FLAG_STRIP_LOW | FILTER_FLAG_STRIP_HIGH);



/*

Results:

|asdf    �_123|

|asdf_123|

*/

?>

dale dot liszka at gmail dot com
09-Jul-2008 04:54


Using the FILTER_CALLBACK requires an array to be passed as the options:



<?php

function toDash($x){

   return str_replace("_","-",$x);

} 



echo filter_var("asdf_123",FILTER_CALLBACK,array("options"=>"toDash"));

// returns 'asdf-123'

?>

John
26-Jul-2007 07:35


I managed to get this to work with PHP 5.1.6 on CentOS 5 with minor difficulty.



1) Download the PECL filter package

2) Extract the tarball

3) phpize the directory

4) ./configure

5) make

6) filter-0.11.0/logical_filters.c:25:31: error: ext/pcre/php_pcre.h: No such file or directory

7) find / -name php_pcre.h

8) Make sure php-devel is installed

9) Edit filter-0.11.0/logical_filters.c and replace "ext/pcre/php_pcre.h" with the absolute path of php_pcre.h

10) make

11) make install

12) add "extension=filter.so" to php.ini

13) Restart Apache

add a note

Function Handling

filter_var_array

Last updated: Fri, 30 Oct 2009