Php/docs/function.filter-var
filter_var
(PHP 5 >= 5.2.0, PHP 7)
filter_var — 使用特定的过滤器过滤一个变量
参数
variable
待过滤的变量。注意:标量的值在过滤前,会被转换成字符串。
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 toFILTER_UNSAFE_RAW
. This will result in no filtering taking place by default.options
一个选项的关联数组,或者按位区分的标示。如果过滤器接受选项,可以通过数组的 "flags" 位去提供这些标示。 对于回调型的过滤器,应该传入 callable。这个回调函数必须接受一个参数,即待过滤的值,并且 返回一个在过滤/净化后的值。
<?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$var = filter_var('oops', FILTER_VALIDATE_BOOLEAN, array('flags' => FILTER_NULL_ON_FAILURE));// callback validate filterfunction foo($value){ // Expected format: Surname, GivenNames if (strpos($value, ", ") === false) return false; list($surname, $givennames) = explode(", ", $value, 2); $empty = (empty($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 一个 filter_var() 的例子
<?phpvar_dump(filter_var('bob@example.com', FILTER_VALIDATE_EMAIL));var_dump(filter_var('http://example.com', FILTER_VALIDATE_URL, FILTER_FLAG_PATH_REQUIRED));?>
以上例程会输出:
string(15) "bob@example.com" bool(false)
参见
- filter_var_array() - 获取多个变量并且过滤它们
- filter_input() - 通过名称获取特定的外部变量,并且可以通过过滤器处理它
- filter_input_array() - 获取一系列外部变量,并且可以通过过滤器处理它们
- Types of filters