php man page for grapheme_substr

GRAPHEME_SUBSTR(3)							 1							GRAPHEME_SUBSTR(3)

grapheme_substr - Return part of a string

       Procedural style

SYNOPSIS
       int grapheme_substr (string  $string, int  $start, [int	$length])

DESCRIPTION
	Return part of a string

PARAMETERS
	      o $string
		- The input string. Must be valid UTF-8.

	      o $start
		- Start position in default grapheme units. If $start is non-negative, the returned string will start at the $start'th position in
		$string, counting from zero. If $start is negative, the returned string will start at the $start'th grapheme unit from the end	of
		string.

	      o $length
		-  Length  in grapheme units. If $length is given and is positive, the string returned will contain at most $length grapheme units
		beginning from $start (depending on the length of string). If $length is given and is negative, then that many grapheme units will
		be  omitted  from  the	end of string (after the start position has been calculated when a start is negative). If $start denotes a
		position beyond this truncation, FALSE will be returned.

RETURN VALUES
	Returns the extracted part of $string.

CHANGELOG
       +--------+---------------------------------------------------+
       |Version |						    |
       |	|						    |
       |	|		     Description		    |
       |	|						    |
       +--------+---------------------------------------------------+
       |  5.4	|						    |
       |	|						    |
       |	|  If $length is given and positive and  the  argu- |
       |	| ment string is shorter than the specified length, |
       |	| all the rest of the string  according  to  $start |
       |	| parameter  is  returned.  Previously,  FALSE	was |
       |	| returned.					    |
       |	|						    |
       +--------+---------------------------------------------------+
EXAMPLES
       Example #1

	      grapheme_substr(3) example

	      <?php

	      $char_a_ring_nfd = "axCCx8A";  // 'LATIN SMALL LETTER A WITH RING ABOVE' (U+00E5) normalization form "D"
	      $char_o_diaeresis_nfd = "oxCCx88"; // 'LATIN SMALL LETTER O WITH DIAERESIS' (U+00F6) normalization form "D"

	      print urlencode(grapheme_substr( "ao" . $char_a_ring_nfd . "bc" . $char_o_diaeresis_nfd . "O", 2, -1 ));
	      ?>

       The above example will output:

       a%CC%8Abco%CC%88

SEE ALSO
       grapheme_extract(3),  Unicode Text Segmentation: Grapheme Cluster Boundaries .

PHP Documentation Group 													GRAPHEME_SUBSTR(3)