php字符串标点等字符截取不乱吗 封装方法

方法一：

/**

+----------------------------------------------------------

* 功能：字符串截取指定长度

* leo.li hengqin2008@qq.com

+----------------------------------------------------------

* @param string $string 待截取的字符串

* @param int $len 截取的长度

* @param int $start 从第几个字符開始截取

* @param boolean $suffix 是否在截取后的字符串后跟上省略号

+----------------------------------------------------------

* @return string 返回截取后的字符串

+----------------------------------------------------------

*/

function cutStr($str, $len = 100, $start = 0, $suffix = 1) {

$str = strip_tags(trim(strip_tags($str)));

$str = str_replace(array("\n", "\t"), "", $str);

$strlen = mb_strlen($str);

while ($strlen) {

$array[] = mb_substr($str, 0, 1, "utf8");

$str = mb_substr($str, 1, $strlen, "utf8");

$strlen = mb_strlen($str);

}

$end = $len + $start;

$str = '';

for ($i = $start; $i < $end; $i++) {

$str.=$array[$i];

}

return count($array) > $len ? ($suffix == 1 ? $str . "…" : $str) : $str;

}

方法二：

header("Content-type:text/html; charset=utf8");

function cut_str($string, $sublen, $start = 0, $code = 'UTF-8')

{

if($code == 'UTF-8')

{

$pa ="/[\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($pa, $string, $t_string); if(count($t_string[0]) - $start > $sublen) return join('', array_slice($t_string[0], $start, $sublen));

return join('', array_slice($t_string[0], $start, $sublen));

}

else

{

$start = $start*2;

$sublen = $sublen*2;

$strlen = strlen($string);

$tmpstr = ''; for($i=0; $i<$strlen; $i++)

{

if($i>=$start && $i<($start+$sublen))

{

if(ord(substr($string, $i, 1))>129)

{

$tmpstr.= substr($string, $i, 2);

}

else

{

$tmpstr.= substr($string, $i, 1);

}

}

if(ord(substr($string, $i, 1))>129) $i++;

}

if(strlen($tmpstr)<$strlen ) $tmpstr.= "";

return $tmpstr;

}

}

$str="我slskjd!fl是总那地方拉伸款到即发";

echo cut_str($str, 8, 5);