filter_var
(PHP 5 >= 5.2.0)
filter_var — Filters a variable with a specified filter
说明
mixed filter_var ( mixed $variable [, int $filter = FILTER_DEFAULT [, mixed $options ]] )参数
- variable
-
Value to filter.
- filter
-
The ID of the filter to apply. The Types of filters manual page lists the available filters.
- 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'));
?>
返回值
Returns the filtered data, or FALSE if the filter fails.
范例
Example #1 A filter_var() example 以上例程会输出：
<?php
var_dump(filter_var('bob@example.com', FILTER_VALIDATE_EMAIL));
var_dump(filter_var('http://example.com', FILTER_VALIDATE_URL, FILTER_FLAG_PATH_REQUIRED));
?>
string(15) "bob@example.com"
bool(false)
参见
- filter_var_array() - Gets multiple variables and optionally filters them
- filter_input() - Gets a specific external variable by name and optionally filters it
- filter_input_array() - Gets external variables and optionally filters them
- Types of filters
- callback 类型的信息
