Web студия "GrandView"

Description

string mb_substr ( string str, int start [, int length [, string encoding]] )

mb_substr() returns the portion of str specified by the start and length parameters.

mb_substr() performs multi-byte safe substr() operation based on number of characters. Position is counted from the beginning of str. First character's position is 0. Second character position is 1, and so on.

If encoding is omitted, internal encoding is assumed.

encoding is character encoding. If it is omitted, internal character encoding is used.

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mb_substr

Silvan
01-Sep-2007 03:30


Passing null as length will not make mb_substr use it's default, instead it will interpret it as 0.

<?php

mb_substr($str,$start,null,$encoding); //Returns '' (empty string) just like substr()

?>

Instead use:

<?php

mb_substr($str,$start,mb_strlen($str),$encoding);

?>

xiaogil at yahoo dot fr
02-Aug-2005 08:33


Thanks Darien from /freenode #php for the following example (a little bit changed).



It just prints the 6th character of $string.

You can replace the digits by the same in japanese, chinese or whatever language to make a test, it works perfect.



<?php

mb_internal_encoding("UTF-8");

$string = "0123456789";

$mystring = mb_substr($string,5,1);

echo $mystring;

?>



(I couldn't replace 0123456789 by chinese numbers for example here, because it's automatically converted into latin digits on this website, look : 

&#38646;&#19968;&#20108;&#19977;&#22235;

&#20116;&#20845;&#19971;&#20843;&#20061;)



gilv

drraf at tlen dot pl
23-Feb-2005 06:44


Note: If borders are out of string - mb_string() returns empty _string_, when function substr() returns _boolean_ false in this case.

Keep this in mind when using "===" comparisions.



Example code:

<?php



var_dump( substr( 'abc', 5, 2 ) ); // returns "false"

var_dump( mb_substr( 'abc', 5, 2 ) ); // returns ""



?>



It's especially confusing when using mbstring with function overloading turned on.

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