grapheme_extract

Here's how to use grapheme_extract() to loop across a UTF-8 string character by character.<?php$str = "سabcक’…";// if the previous line didn't come through, the string contained://U+0633,U+0061,U+0062,U+0063,U+0915,U+2019,U+2026$n = 0;for (    $start = 0, $next = 0, $maxbytes = strlen($str), $c = '';        $start < $maxbytes;        $c = grapheme_extract($str, 1, GRAPHEME_EXTR_MAXCHARS , ($start = $next), $next)    ){    if (empty($c))        continue;    echo "This utf8 character is " . strlen($c) . " bytes long and its first byte is " . ord($c[0]) . "\n";    $n++;}echo "$n UTF-8 characters in a string of $maxbytes bytes!\n";// Should print: 7 UTF8 characters in a string of 14 bytes!?>

The other comments on this page were helpful for me.However, consider using something better than empty($value) when checking the value returned by grapheme_extract since it could as well return something like "0" (which of course evaluates to false).

Looping through grapheme clusters:<?php// Example taken from Rust documentation: https://doc.rust-lang.org/book/ch08-02-strings.html#bytes-and-scalar-values-and-grapheme-clusters-oh-my$str = "नमस्ते";// Alternatively://$str = pack('C*', ...[224, 164, 168, 224, 164, 174, 224, 164, 184, 224, 165, 141, 224, 164, 164, 224, 165, 135]);$next = 0;$maxbytes = strlen($str);var_dump($str);while ($next < $maxbytes) {    $char = grapheme_extract($str, 1, GRAPHEME_EXTR_COUNT, $next, $next);    if (empty($char)) {        continue;    }    echo "{$char} - This utf8 character is " . strlen($char) . ' bytes long', PHP_EOL;}//string(18) "नमस्ते"//न - This utf8 character is 3 bytes long//म - This utf8 character is 3 bytes long//स् - This utf8 character is 6 bytes long//ते - This utf8 character is 6 bytes long?>