Grapheme Funktionen
PHP-Handbuch

grapheme_extract

Function to extract a sequence of default grapheme clusters from a text buffer, which must be encoded in UTF-8.

Beschreibung

Prozeduraler Stil

string grapheme_extract ( string $haystack , int $size [, int $extract_type [, int $start = 0 [, int &$next ]]] )

Function to extract a sequence of default grapheme clusters from a text buffer, which must be encoded in UTF-8.

Parameter-Liste

haystack

String to search.

size

Maximum number items - based on the $extract_type - to return.

extract_type

Defines the type of units referred to by the $size parameter:

  • GRAPHEME_EXTR_COUNT (default) - $size is the number of default grapheme clusters to extract.
  • GRAPHEME_EXTR_MAXBYTES - $size is the maximum number of bytes returned.
  • GRAPHEME_EXTR_MAXCHARS - $size is the maximum number of UTF-8 characters returned.

start

Starting position in $haystack in bytes - if given, it must be zero or a positive value that is less than or equal to the length of $haystack in bytes, or a negative value that counts from the end of $haystack. If $start does not point to the first byte of a UTF-8 character, the start position is moved to the next character boundary.

next

Reference to a value that will be set to the next starting position. When the call returns, this may point to the first byte position past the end of the string.

Rückgabewerte

A string starting at offset $start and ending on a default grapheme cluster boundary that conforms to the $size and $extract_type specified.

Changelog

Version Beschreibung
7.1.0 Support for negative starts has been added.

Beispiele

Beispiel #1 grapheme_extract example

<?php

$char_a_ring_nfd = "a\xCC\x8A";  // 'LATIN SMALL LETTER A WITH RING ABOVE' (U+00E5) normalization form "D"
$char_o_diaeresis_nfd = "o\xCC\x88"; // 'LATIN SMALL LETTER O WITH DIAERESIS' (U+00F6) normalization form "D"

print urlencode(grapheme_extract( $char_a_ring_nfd . $char_o_diaeresis_nfd, 1, GRAPHEME_EXTR_COUNT, 2));

?>

Das oben gezeigte Beispiel erzeugt folgende Ausgabe:

o%CC%88