filter_var

Filters a variable with a specified filter

Description

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

Parameters

variable

Value to filter. Note that scalar values are converted to string internally before they are filtered.

filter

The ID of the filter to apply. The Types of filters manual page lists the available filters.

If omitted, FILTER_DEFAULT will be used, which is equivalent to FILTER_UNSAFE_RAW. This will result in no filtering taking place by default.

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, callable 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_BOOLEANFILTER_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 validate filter
function foo($value)
{
    
// Expected format: Surname, GivenNames
    
if (strpos($value", ") === false) return false;
    list(
$surname$givennames) = explode(", "$value2);
    
$empty = (empty($surname) || empty($givennames));
    
$notstrings = (!is_string($surname) || !is_string($givennames));
    if (
$empty || $notstrings) {
        return 
false;
    } else {
        return 
$value;
    }
}
$var filter_var('Doe, Jane Sue'FILTER_CALLBACK, array('options' => 'foo'));
?>

Return Values

Returns the filtered data, or FALSE if the filter fails.

Examples

Example #1 A filter_var example

<?php
var_dump
(filter_var('bob@example.com'FILTER_VALIDATE_EMAIL));
var_dump(filter_var('http://example.com'FILTER_VALIDATE_URLFILTER_FLAG_PATH_REQUIRED));
?>

The above example will output:

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

See Also