Predefined Constants

The constants below are defined by this extension, and will only be available when the extension has either been compiled into PHP or dynamically loaded at runtime.

INPUT_POST (int)

POST variables.

INPUT_GET (int)

GET variables.

INPUT_COOKIE (int)

COOKIE variables.

INPUT_ENV (int)

ENV variables.

INPUT_SERVER (int)

SERVER variables.

INPUT_SESSION (int)

SESSION variables. (not implemented yet)

INPUT_REQUEST (int)

REQUEST variables. (not implemented yet)

FILTER_FLAG_NONE (int)

No flags.

FILTER_REQUIRE_SCALAR (int)

Flag used to require scalar as input

FILTER_REQUIRE_ARRAY (int)

Require an array as input.

FILTER_FORCE_ARRAY (int)

Always returns an array.

FILTER_NULL_ON_FAILURE (int)

Use NULL instead of FALSE on failure.

FILTER_VALIDATE_INT (int)

ID of "int" filter.

FILTER_VALIDATE_BOOL (int)

Alias of FILTER_VALIDATE_BOOLEAN.

FILTER_VALIDATE_BOOLEAN (int)

ID of "boolean" filter.

FILTER_VALIDATE_FLOAT (int)

ID of "float" filter.

FILTER_VALIDATE_REGEXP (int)

ID of "validate_regexp" filter.

FILTER_VALIDATE_URL (int)

ID of "validate_url" filter.

FILTER_VALIDATE_DOMAIN (int)

ID of "validate_domain" filter. (Available as of PHP 7.0.0)

FILTER_VALIDATE_EMAIL (int)

ID of "validate_email" filter.

FILTER_VALIDATE_IP (int)

ID of "validate_ip" filter.

FILTER_VALIDATE_MAC (int)

ID of "validate_mac_address" filter.

FILTER_DEFAULT (int)

ID of default ("unsafe_raw") filter. This is equivalent to FILTER_UNSAFE_RAW.

FILTER_UNSAFE_RAW (int)

ID of "unsafe_raw" filter.

FILTER_SANITIZE_STRING (int)

ID of "string" filter. (Deprecated as of PHP 8.1.0, use htmlspecialchars() instead.)

FILTER_SANITIZE_STRIPPED (int)

ID of "stripped" filter. (Deprecated as of PHP 8.1.0, use htmlspecialchars() instead.)

FILTER_SANITIZE_ENCODED (int)

ID of "encoded" filter.

FILTER_SANITIZE_SPECIAL_CHARS (int)

ID of "special_chars" filter.

FILTER_SANITIZE_EMAIL (int)

ID of "email" filter.

FILTER_SANITIZE_URL (int)

ID of "url" filter.

FILTER_SANITIZE_NUMBER_INT (int)

ID of "number_int" filter.

FILTER_SANITIZE_NUMBER_FLOAT (int)

ID of "number_float" filter.

FILTER_SANITIZE_MAGIC_QUOTES (int)

ID of "magic_quotes" filter. (DEPRECATED as of PHP 7.3.0 and REMOVED as of PHP 8.0.0, use FILTER_SANITIZE_ADD_SLASHES instead.)

FILTER_SANITIZE_ADD_SLASHES (int)

ID of "add_slashes" filter. (Available as of PHP 7.3.0)

FILTER_CALLBACK (int)

ID of "callback" filter.

FILTER_FLAG_ALLOW_OCTAL (int)

Allow octal notation (0[0-7]+) in "int" filter.

FILTER_FLAG_ALLOW_HEX (int)

Allow hex notation (0x[0-9a-fA-F]+) in "int" filter.

FILTER_FLAG_STRIP_LOW (int)

Strip characters with ASCII value less than 32.

FILTER_FLAG_STRIP_HIGH (int)

Strip characters with ASCII value greater than 127.

FILTER_FLAG_STRIP_BACKTICK (int)

Strips backtick characters.

FILTER_FLAG_ENCODE_LOW (int)

Encode characters with ASCII value less than 32.

FILTER_FLAG_ENCODE_HIGH (int)

Encode characters with ASCII value greater than 127.

FILTER_FLAG_ENCODE_AMP (int)

Encode &.

FILTER_FLAG_NO_ENCODE_QUOTES (int)

Don't encode ' and ".

FILTER_FLAG_EMPTY_STRING_NULL (int)

(No use for now.)

FILTER_FLAG_ALLOW_FRACTION (int)

Allow fractional part in "number_float" filter.

FILTER_FLAG_ALLOW_THOUSAND (int)

Allow thousand separator (,) in "number_float" filter.

FILTER_FLAG_ALLOW_SCIENTIFIC (int)

Allow scientific notation (e, E) in "number_float" filter.

FILTER_FLAG_PATH_REQUIRED (int)

Require path in "validate_url" filter.

FILTER_FLAG_QUERY_REQUIRED (int)

Require query in "validate_url" filter.

FILTER_FLAG_SCHEME_REQUIRED (int)

Require scheme in "validate_url" filter. (Deprecated as of PHP 7.3.0 and removed as of PHP 8.0.0, as it is implied in the filter already.)

FILTER_FLAG_HOST_REQUIRED (int)

Require host in "validate_url" filter. (Deprecated as of PHP 7.3.0 and removed as of PHP 8.0.0, as it is implied in the filter already.)

FILTER_FLAG_HOSTNAME (int)

Require hostnames to start with an alphanumeric character and contain only alphanumerics or hyphens. (Available as of PHP 7.0.0)

FILTER_FLAG_IPV4 (int)

Allow only IPv4 address in "validate_ip" filter.

FILTER_FLAG_IPV6 (int)

Allow only IPv6 address in "validate_ip" filter.

FILTER_FLAG_NO_RES_RANGE (int)

Deny reserved addresses in "validate_ip" filter.

FILTER_FLAG_NO_PRIV_RANGE (int)

Deny private addresses in "validate_ip" filter.

FILTER_FLAG_EMAIL_UNICODE (int)

Accepts Unicode characters in the local part in "validate_email" filter. (Available as of PHP 7.1.0)