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run code in 300+ PHP versions simultaneously
<?php function seems_utf8($str) { $length = strlen($str); for ($i = 0; $i < $length; $i++) { $c = ord($str[$i]); if ($c < 0x80) $n = 0; elseif (($c & 0xE0) == 0xC0) $n = 1; elseif (($c & 0xF0) == 0xE0) $n = 2; elseif (($c & 0xF8) == 0xF0) $n = 3; elseif (($c & 0xFC) == 0xF8) $n = 4; elseif (($c & 0xFE) == 0xFC) $n = 5; else return false; for ($j=0; $j<$n; $j++) { if ((++$i == $length) || ((ord($str[$i]) & 0xC0) != 0x80)) return false; } } return true; } var_dump( seems_utf8("asd") );
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
bool(true)

preferences:
190.62 ms | 403 KiB | 198 Q