UTF-8下面截取中文字符。

<?php//支持中文的substr(string,length[,start])//“反斜杠”被博客系统过滤了，请在每个 x 前面添加“反斜杠”function cnsubstr($l1,$l2,$l3=0){    $I2 = "/[x01-x7f]|[xc2-xdf][x80-xbf]|xe0[xa0-xbf][x80-xbf]|[xe1-xef][x80-xbf][x80-xbf]|xf0[x90-xbf][x80-xbf][x80-xbf]|[xf1-xf7][x80-xbf][x80-xbf][x80-xbf]/";    preg_match_all($I2,$l1,$I3);       if (count($I3[0]) - $l3 > $l2) {           return implode('',array_slice($I3[0],$l3,$l2))."...";       }       return implode('',array_slice($I3[0],$l3,$l2));}//计算中文字符长度function len($l1){    $I2 = "/[x01-x7f]|[xc2-xdf][x80-xbf]|xe0[xa0-xbf][x80-xbf]|[xe1-xef][x80-xbf][x80-xbf]|xf0[x90-xbf][x80-xbf][x80-xbf]|[xf1-xf7][x80-xbf][x80-xbf][x80-xbf]/";    preg_match_all($I2,$l1,$I3);       return count($I3[0]);}?>

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