3v4l.org

run code in 300+ PHP versions simultaneously
<?php function substr_utf8($string, $start, $length) { $chars = $string; $i=0; do { if (preg_match ("/[0-9a-zA-Z]/", $chars[$i])){ $m++; } else { $n++; }//非英文字节, $k = $n/3 + $m/2; $l = $n/3 + $m; $i++; } while ($k < $length); $str1 = mb_substr($string,$start,$l,'utf-8'); return $str1; } $a = '测试这是一个测试'; $a = 'xxxxbbbbbnnn'; $b = substr_utf8($a,0,5); var_dump($b); ?>
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Warning: Undefined variable $m in /in/Ptef2 on line 8 Warning: Undefined variable $n in /in/Ptef2 on line 12 Warning: Undefined variable $n in /in/Ptef2 on line 13 Warning: Undefined variable $n in /in/Ptef2 on line 12 Warning: Undefined variable $n in /in/Ptef2 on line 13 Warning: Undefined variable $n in /in/Ptef2 on line 12 Warning: Undefined variable $n in /in/Ptef2 on line 13 Warning: Undefined variable $n in /in/Ptef2 on line 12 Warning: Undefined variable $n in /in/Ptef2 on line 13 Warning: Undefined variable $n in /in/Ptef2 on line 12 Warning: Undefined variable $n in /in/Ptef2 on line 13 Warning: Undefined variable $n in /in/Ptef2 on line 12 Warning: Undefined variable $n in /in/Ptef2 on line 13 Warning: Undefined variable $n in /in/Ptef2 on line 12 Warning: Undefined variable $n in /in/Ptef2 on line 13 Warning: Undefined variable $n in /in/Ptef2 on line 12 Warning: Undefined variable $n in /in/Ptef2 on line 13 Warning: Undefined variable $n in /in/Ptef2 on line 12 Warning: Undefined variable $n in /in/Ptef2 on line 13 Warning: Undefined variable $n in /in/Ptef2 on line 12 Warning: Undefined variable $n in /in/Ptef2 on line 13 string(10) "xxxxbbbbbn"
Output for 5.0.4 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.25, 7.4.27 - 7.4.33
Notice: Undefined variable: m in /in/Ptef2 on line 8 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 string(10) "xxxxbbbbbn"
Output for 7.3.32 - 7.3.33, 7.4.26
string(10) "xxxxbbbbbn"
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.3
Notice: Undefined variable: m in /in/Ptef2 on line 8 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 Notice: Undefined variable: n in /in/Ptef2 on line 12 Notice: Undefined variable: n in /in/Ptef2 on line 13 string(10) "xxxxbbbbbn"
preferences:
211.95 ms | 404 KiB | 329 Q