PHP 过滤器函数

PHP过滤器介绍

该 PHP 过滤器用于验证和过滤来自不安全来源的数据，例如用户输入。

安装

从 PHP 5.2.0 开始，默认启用过滤功能。使用这些功能无需安装。

运行时配置

这些函数的行为受 php.ini 中的设置影响：

Name	Description	Default	Changeable
filter.default	Filter all $_GET, $_POST, $_COOKIE, $_REQUEST and $_SERVER data by this filter. Accepts the name of the filter you like to use by default. See the filter list for the list of the filter names	"unsafe_raw"	PHP_INI_PERDIR
filter.default_flags	Default flags to apply when the default filter is set. This is set to FILTER_FLAG_NO_ENCODE_QUOTES by default for backwards compatibility reasons	NULL	PHP_INI_PERDIR

PHP 过滤函数

Function	Description
filter_has_var()	Checks whether a variable of a specified input type exist
filter_id()	Returns the filter ID of a specified filter name
filter_input()	Gets an external variable (e.g. from form input) and optionally filters it
filter_input_array()	Gets external variables (e.g. from form input) and optionally filters them
filter_list()	Returns a list of all supported filter names
filter_var()	Filters a variable with a specified filter
filter_var_array()	Gets multiple variables and filter them

PHP 预定义过滤器常量

Constant	Description
INPUT_POST	POST variables
INPUT_GET	GET variables
INPUT_COOKIE	COOKIE variables
INPUT_ENV	ENV variables
INPUT_SERVER	SERVER variables
FILTER_DEFAULT	Do nothing, optionally strip/encode special characters. Equivalent to FILTER_UNSAFE_RAW
FILTER_FLAG_NONE	Allows no flags
FILTER_FLAG_ALLOW_OCTAL	Only for inputs that starts with a zero (0) as octal numbers. This only allows the succeeding digits to be 0-7
FILTER_FLAG_ALLOW_HEX	Only for inputs that starts with 0x/0X as hexadecimal numbers. This only allows succeeding characters to be a-fA-F0-9
FILTER_FLAG_STRIP_LOW	Strip characters with ASCII value lower than 32
FILTER_FLAG_STRIP_HIGH	Strip characters with ASCII value greater than 127
FILTER_FLAG_ENCODE_LOW	Encode characters with ASCII value lower than 32
FILTER_FLAG_ENCODE_HIGH	Encode characters with ASCII value greater than 127
FILTER_FLAG_ENCODE_AMP	Encode &
FILTER_FLAG_NO_ENCODE_QUOTES	Do not encode ' and "
FILTER_FLAG_EMPTY_STRING_NULL	Not in use
FILTER_FLAG_ALLOW_FRACTION	Allows a period (.) as a fractional separator in numbers
FILTER_FLAG_ALLOW_THOUSAND	Allows a comma (,) as a thousands separator in numbers
FILTER_FLAG_ALLOW_SCIENTIFIC	Allows an e or E for scientific notation in numbers
FILTER_FLAG_PATH_REQUIRED	The URL must contain a path part
FILTER_FLAG_QUERY_REQUIRED	The URL must contain a query string
FILTER_FLAG_IPV4	Allows the IP address to be in IPv4 format
FILTER_FLAG_IPV6	Allows the IP address to be in IPv6 format
FILTER_FLAG_NO_RES_RANGE	Fails validation for the reserved IPv4 ranges: 0.0.0.0/8, 169.254.0.0/16, 127.0.0.0/8 and 240.0.0.0/4, and for the reserved IPv6 ranges: ::1/128, ::/128, ::ffff:0:0/96 and fe80::/10
FILTER_FLAG_NO_PRIV_RANGE	Fails validation for the private IPv4 ranges: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16, and for the IPv6 addresses starting with FD or FC
FILTER_FLAG_EMAIL_UNICODE	Allows the local part of the email address to contain Unicode characters
FILTER_REQUIRE_SCALAR	The value must be a scalar
FILTER_REQUIRE_ARRAY	The value must be an array
FILTER_FORCE_ARRAY	Treats a scalar value as array with the scalar value as only element
FILTER_NULL_ON_FAILURE	Return NULL on failure for unrecognized boolean values
FILTER_VALIDATE_BOOLEAN	Validates a boolean
FILTER_VALIDATE_EMAIL	Validates value as a valid e-mail address
FILTER_VALIDATE_FLOAT	Validates value as float
FILTER_VALIDATE_INT	Validates value as integer
FILTER_VALIDATE_IP	Validates value as IP address
FILTER_VALIDATE_MAC	Validates value as MAC address
FILTER_VALIDATE_REGEXP	Validates value against a regular expression
FILTER_VALIDATE_URL	Validates value as URL
FILTER_SANITIZE_EMAIL	Removes all illegal characters from an e-mail address
FILTER_SANITIZE_ENCODED	Removes/Encodes special characters
FILTER_SANITIZE_MAGIC_QUOTES	Apply addslashes()
FILTER_SANITIZE_NUMBER_FLOAT	Remove all characters, except digits, +- signs, and optionally .,eE
FILTER_SANITIZE_NUMBER_INT	Removes all characters except digits and + - signs
FILTER_SANITIZE_SPECIAL_CHARS	Removes special characters
FILTER_SANITIZE_STRING	Removes tags/special characters from a string
FILTER_SANITIZE_STRIPPED	Alias of FILTER_SANITIZE_STRING
FILTER_SANITIZE_URL	Removes all illegal character from a URL
FILTER_UNSAFE_RAW	Do nothing, optionally strip/encode special characters
FILTER_CALLBACK	Call a user-defined function to filter data