mb_split
I found this function to be extremely useful.
Here is a practical example, showing the difference between substr(), mb_substr() and mb_strcut():
<?php
mb_internal_encoding('UTF-8');
$string = 'cioèòà';
var_dump(
substr($string, 0, 6),
mb_substr($string, 0, 6),
mb_strcut($string, 0, 6)
);
?>
Output:
string(6) "cioè?"
string(9) "cioèòà"
string(5) "cioè"
Explanation:
$string is long 9 bytes
c - 1 byte
i - 1 byte
o - 1 byte
è - 2 bytes
ò - 2 bytes
à - 2 bytes
substr() works with bytes, so it returns a string which is exactly 6 bytes long. Thus, it truncates the ò character.
mb_substr(), instead, works with characters, so it returns a string which is exactly 6 characters long (but in this case is 9 bytes long).
mb_strcut() works exactly as substr(), but, if the last byte appears to be truncated, it simply omits the character.
When you use
$string = mb_strcut($string, 6);
you can know for sure that strlen($string) <= 6. But no unicode characters will be truncated.
I hope my comment could finally be a simple explanation.
mb_strcut
(PHP 4 >= 4.0.6, PHP 5)
mb_strcut — 文字列の一部を得る
説明
string mb_strcut
( string $str
, int $start
[, int $length
[, string $encoding
]] )
mb_strcut() は、mb_substr() と同じ処理を異なった方法で行います。位置 start がマルチバイト文字の 2 バイト目以降で ある場合、マルチバイト文字の最初のバイトから開始されます。
この関数は、length より短く、 かつマルチバイト文字列の一部でないかシフトシーケンスの中にない文字を 取りだします。
パラメータ
- str
-
取り出しの対象となる文字列。
- start
-
取り出しの開始位置。
- length
-
取り出す長さ。
- encoding
-
encoding パラメータには文字エンコーディングを指定します。省略した場合は、 内部文字エンコーディングを使用します。
返り値
mb_strcut() は、 start および length パラメータで指定した str の一部を返します。
add a note
User Contributed Notesmb_strcut
egoalesum at IHATEBOTS dot youarchive dot it
21-May-2009 04:07
21-May-2009 04:07
t dot starling at physics dot unimelb dot edu dot au
27-Aug-2004 11:01
27-Aug-2004 11:01
What the manual and the first commenter are trying to say is that mb_strcut uses byte offsets, as opposed to mb_substr which uses character offsets.
Both mb_strcut and mb_substr appear to treat negative and out-of-range offsets and lengths in the basically the same way as substr. An exception is that if start is too large, an empty string will be returned rather than FALSE. Testing indicates that mb_strcut first works out start and end byte offsets, then moves each offset left to the nearest character boundary.
oyag02 at yahoo dot co dot jp
26-Sep-2003 10:53
26-Sep-2003 10:53
diffrence between mb_substr and mb_substr
example:
mb_strcut('I_ROHA', 1, 2) returns 'I_'. Treated as byte stream.
mb_substr('I_ROHA', 1, 2) returns 'ROHA' Treated as character stream.
# 'I_' 'RO' 'HA' means multi-byte character