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filter_var

(PHP 5 >= 5.2.0, PHP 7, PHP 8)

filter_var — Filters a variable with a specified filter

Descrizione

filter_var(mixed $value, int $filter = FILTER_DEFAULT, array|int $options = 0): mixed

Filter a variable using a FILTER_VALIDATE_* validation filters, a FILTER_SANITIZE_* sanitization filters, or a custom filter.

Elenco dei parametri

value
Value to filter.
Avviso

Scalar values are converted to string internally before they are filtered.

filter
The filter to apply. Can be a validation filter by using one of the FILTER_VALIDATE_* constants, a sanitization filter by using one of the FILTER_SANITIZE_* or FILTER_UNSAFE_RAW, or a custom filter by using FILTER_CALLBACK.

Nota: The default is FILTER_DEFAULT, which is an alias of FILTER_UNSAFE_RAW. This will result in no filtering taking place by default.

options
Either an associative array of options, or a bitmask of filter flag constants FILTER_FLAG_*. If the filter accepts options, flags can be provided by using the "flags" field of array.

Valori restituiti

On success returns the filtered data. On failure false is returned, unless the FILTER_NULL_ON_FAILURE flag is used, in which case null is returned.

Esempi

Example #1 A filter_var() example

<?php
var_dump(filter_var('bob@example.com', FILTER_VALIDATE_EMAIL));
var_dump(filter_var('https://example.com', FILTER_VALIDATE_URL, FILTER_FLAG_PATH_REQUIRED));
?>

Il precedente esempio visualizzerà:

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

Example #2 Example validating entries of an array

<?php
$emails = [
"bob@example.com",
"test@example.local",
"invalidemail"
];

var_dump(filter_var($emails, FILTER_VALIDATE_EMAIL, FILTER_REQUIRE_ARRAY));
?>

Il precedente esempio visualizzerà:

array(3) {
  [0]=>
  string(15) "bob@example.com"
  [1]=>
  string(18) "test@example.local"
  [2]=>
  bool(false)
}

Example #3 Example of passing an array for options

<?php

$options = [
'options' => [
'min_range' => 10,
],
'flags' => FILTER_FLAG_ALLOW_OCTAL,
];

var_dump(filter_var('0755', FILTER_VALIDATE_INT, $options));
var_dump(filter_var('011', FILTER_VALIDATE_INT, $options));

?>

Il precedente esempio visualizzerà:

int(493)
bool(false)

Example #4 Providing flags either directly or via an array

<?php

$str = 'string';

var_dump(filter_var($str, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE));
var_dump(filter_var($str, FILTER_VALIDATE_BOOLEAN, ['flags' => FILTER_NULL_ON_FAILURE]));

?>

Il precedente esempio visualizzerà:

NULL
NULL

Vedere anche: