Runtime Configuration
The behaviour of these functions is affected by settings in php.ini.
| Name | Default | Changeable | Changelog |
|---|---|---|---|
| mbstring.language | "neutral" | PHP_INI_ALL | Available since PHP 4.3.0. PHP_INI_PERDIR in PHP <= 5.2.6 |
| mbstring.detect_order | NULL | PHP_INI_ALL | Available since PHP 4.0.6. |
| mbstring.http_input | "pass" | PHP_INI_ALL | Available since PHP 4.0.6. |
| mbstring.http_output | "pass" | PHP_INI_ALL | Available since PHP 4.0.6. |
| mbstring.internal_encoding | NULL | PHP_INI_ALL | Available since PHP 4.0.6. |
| mbstring.script_encoding | NULL | PHP_INI_ALL | Available since PHP 4.3.0. Removed in PHP 5.4.0. Use zend.script_encoding instead. |
| mbstring.substitute_character | NULL | PHP_INI_ALL | Available since PHP 4.0.6. |
| mbstring.func_overload | "0" | PHP_INI_SYSTEM | PHP_INI_PERDIR from PHP 4.3 to 5.2.6, otherwise PHP_INI_SYSTEM. Available since PHP 4.2.0. |
| mbstring.encoding_translation | "0" | PHP_INI_PERDIR | Available since PHP 4.3.0. |
| mbstring.strict_detection | "0" | PHP_INI_ALL | Available since PHP 5.1.2. |
Here's a short explanation of the configuration directives.
-
mbstring.languagestring -
The default national language setting (NLS) used in mbstring. Note that this option automagically defines mbstring.internal_encoding and mbstring.internal_encoding should be placed after mbstring.language in php.ini
-
mbstring.encoding_translationboolean -
Enables the transparent character encoding filter for the incoming HTTP queries, which performs detection and conversion of the input encoding to the internal character encoding.
-
mbstring.internal_encodingstring -
Defines the default internal character encoding. Since PHP 5.6.0, if this setting is empty, default_charset is used.
-
mbstring.http_inputstring -
Defines the default HTTP input character encoding.
-
mbstring.http_outputstring -
Defines the default HTTP output character encoding.
-
mbstring.detect_orderstring -
Defines default character code detection order. See also mb_detect_order().
-
mbstring.substitute_characterstring -
Defines character to substitute for invalid character encoding.
-
mbstring.func_overloadstring -
Overloads a set of single byte functions by the mbstring counterparts. See Function overloading for more information.
This setting can only be changed from the php.ini file.
-
mbstring.strict_detectionboolean -
Enables the strict encoding detection.
According to the » HTML 4.01 specification, Web browsers are allowed to encode a form being submitted with a character encoding different from the one used for the page. See mb_http_input() to detect character encoding used by browsers.
Although popular browsers are capable of giving a reasonably accurate guess to the character encoding of a given HTML document, it would be better to set the charset parameter in the Content-Type HTTP header to the appropriate value by header() or default_charset ini setting.
Example #1 php.ini setting examples
; Set default language
mbstring.language = Neutral; Set default language to Neutral(UTF-8) (default)
mbstring.language = English; Set default language to English
mbstring.language = Japanese; Set default language to Japanese
;; Set default internal encoding
;; Note: Make sure to use character encoding works with PHP
mbstring.internal_encoding = UTF-8 ; Set internal encoding to UTF-8
;; HTTP input encoding translation is enabled.
mbstring.encoding_translation = On
;; Set default HTTP input character encoding
;; Note: Script cannot change http_input setting.
mbstring.http_input = pass ; No conversion.
mbstring.http_input = auto ; Set HTTP input to auto
; "auto" is expanded according to mbstring.language
mbstring.http_input = SJIS ; Set HTTP input to SJIS
mbstring.http_input = UTF-8,SJIS,EUC-JP ; Specify order
;; Set default HTTP output character encoding
mbstring.http_output = pass ; No conversion
mbstring.http_output = UTF-8 ; Set HTTP output encoding to UTF-8
;; Set default character encoding detection order
mbstring.detect_order = auto ; Set detect order to auto
mbstring.detect_order = ASCII,JIS,UTF-8,SJIS,EUC-JP ; Specify order
;; Set default substitute character
mbstring.substitute_character = 12307 ; Specify Unicode value
mbstring.substitute_character = none ; Do not print character
mbstring.substitute_character = long ; Long Example: U+3000,JIS+7E7E
Example #2 php.ini setting for EUC-JP users
;; Disable Output Buffering output_buffering = Off ;; Set HTTP header charset default_charset = EUC-JP ;; Set default language to Japanese mbstring.language = Japanese ;; HTTP input encoding translation is enabled. mbstring.encoding_translation = On ;; Set HTTP input encoding conversion to auto mbstring.http_input = auto ;; Convert HTTP output to EUC-JP mbstring.http_output = EUC-JP ;; Set internal encoding to EUC-JP mbstring.internal_encoding = EUC-JP ;; Do not print invalid characters mbstring.substitute_character = none
Example #3 php.ini setting for SJIS users
;; Enable Output Buffering output_buffering = On ;; Set mb_output_handler to enable output conversion output_handler = mb_output_handler ;; Set HTTP header charset default_charset = Shift_JIS ;; Set default language to Japanese mbstring.language = Japanese ;; Set http input encoding conversion to auto mbstring.http_input = auto ;; Convert to SJIS mbstring.http_output = SJIS ;; Set internal encoding to EUC-JP mbstring.internal_encoding = EUC-JP ;; Do not print invalid characters mbstring.substitute_character = none
Коментарии
String literals in the PHP script are encoded with the same encoding that the PHP file was saved with. This is not affected by default_charset or other .ini settings.
Scenario: The default_charset is KOI8-R, and there is a text file "input.txt" containing the string "Это текст для поиска." in KOI8-R encoding.
A PHP script is written:
<?php
// mb_internal_encoding('KOI8-R');
$string = 'текст.';
$data = file_get_contents('input.txt');
echo mb_strpos($data, $string);
?>
But unfortunately it was saved as UTF-8.
It doesn't work; mb_strpos() returns false because it can't find the UTF-8-encoded "текст" inside the KOI8-R-encoded "Это текст для поиска.".
Adjusting the default_charset had no effect. Not even fiddling with mb_internal_encoding could fix it, simply because the strings involved had *different* encodings and without actually changing one of them they just weren't going to match.
Either re-save the source file as KOI8-R to match the data file, or re-save the data file as UTF-8 to match the source code. Only then will the script properly echo '4'.
The documentation is vague, on WHAT precisely the valid "NLS" language strings are that are valid for "mbstring.language".
According to function.mb-language the values are "Japanese", "ja", "English", "en", or "uni" for UTF-8.
On the other hand, the sample on this current page omits "uni" but introduces "Neutral" as an undocumented option - which is also the default value:
<?php
var_dump( mb_language() ); // "neutral" (default if not set)
var_dump( mb_language( 'uni' ) ); // TRUE, valid language string
var_dump( mb_language() ); // "uni"
var_dump( mb_language( 'neutral' ) ); // TRUE, valid language string
var_dump( mb_language() ); // "neutral"
?>