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(PHP 4 >= 4.0.6, PHP 5, PHP 7, PHP 8)

mb_detect_orderSet/Get character encoding detection order


mb_detect_order(array|string|null $encoding = null): array|bool

Sets the automatic character encoding detection order to encoding.



encoding is an array or comma separated list of character encoding. See supported encodings.

If encoding is omitted or null, it returns the current character encoding detection order as array.

This setting affects mb_detect_encoding() and mb_send_mail().

mbstring currently implements the following encoding detection filters. If there is an invalid byte sequence for the following encodings, encoding detection will fail.

UTF-8, UTF-7, ASCII, EUC-JP,SJIS, eucJP-win, SJIS-win, JIS, ISO-2022-JP

For ISO-8859-*, mbstring always detects as ISO-8859-*.

For UTF-16, UTF-32, UCS2 and UCS4, encoding detection will fail always.

Return Values

When setting the encoding detection order, true is returned on success or false on failure.

When getting the encoding detection order, an ordered array of the encodings is returned.


Version Description
8.0.0 encoding is nullable now.


Example #1 mb_detect_order() examples

/* Set detection order by enumerated list */

/* Set detection order by array */
$ary[] = "ASCII";
$ary[] = "JIS";
$ary[] = "EUC-JP";

/* Display current detection order */
echo implode(", ", mb_detect_order());

Example #2 Example showing useless detect orders

; Always detect as ISO-8859-1
detect_order = ISO-8859-1, UTF-8

; Always detect as UTF-8, since ASCII/UTF-7 values are 
; valid for UTF-8
detect_order = UTF-8, ASCII, UTF-7

See Also

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User Contributed Notes 1 note

4 months ago
Perhaps obvious to most everyone, but the
default filter list was shorter than I expected:
['ASCII','UTF-8'], in that order.

c. 2024, 60% of websites globally declared charset 'UTF-8'
So if you're experimenting with multibyte encodings other than UTF-8, you have to specify your detect_order, choosing from the list of implemented filters.
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