Filter 函数
PHP 手册

filter_var

(PHP 5 >= 5.2.0)

filter_varFilters 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, 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'));
?>

返回值

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

范例

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));
?>

以上例程会输出:

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

参见


Filter 函数
PHP 手册