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.
A string starting at offset $start and ending on a default grapheme cluster boundary that conforms to the $size and $extract_type specified.
- string $haystack: String to search.
- int $size: Maximum number items - based on the $extract_type - to return.
- int $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.
- int $start [ = 0]: 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 $start does not point to the first byte of a UTF-8 character, the start position is moved to the next character boundary.
- int &$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.
Example #1 grapheme_extract() example
$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));
|7.1.0||Support for negative |