?php
/*
@UTF-8编码的字符可能由1~3个字节组成。
*/
/*--------------------------方法一截取中文字符串方法------------------------------*/
function msubstr($str, $start, $len)
{
$tmpstr = "";
$strlen = $start + $len;
for ($i = 0; $i $strlen; $i++) {
if (ord(substr($str, $i, 1)) > 0xa0) //ord()函数返回字符串的第一个字符的ASCII值
{
$tmpstr .= substr($str, $i, 2);
$i++;
} else {
$tmpstr .= substr($str, $i, 1);
}
}
return $tmpstr;
}
/*----------------------------第二种方法-----------------------------------*/
//截取的是UTF-8字符串
function utf_substr($str, $len)
{
$new_str = [];
for ($i = 0; $i $len; $i++) {
$tem_str = substr($str, 0, 1);
if (ord($tem_str > 127)) {
$i++;
if ($i $len) {
$new_str[] = substr($str, 0, 3);
$str = substr($str, 3);
}
} else {
$new_str[] = substr($str, 0, 1);
$str = substr($str, 1);
}
}
return join($new_str);//join()函数把数组元素组合为一个字符串
}
/*-------------------------------------第三种方法(UTF-8)--------------------------------*/
function cutstr($string, $length)
{
preg_match_all("/[\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]/", $string, $info);
$wordscut = "";
$j = 0;
for ($i = 0; $i count($info[0]); $i++) {
$wordscut .= $info[0][$i];
$j = ord($info[0][$i]) > 127 ? $j + 2 : $j + 1;
if ($j > $length - 3) {
return $wordscut . "...";
}
}
return join('', $info[0]);
}
$string = "312哈哈，这个组合很难切割哦";
echo cutstr($string, 10);
/*---------------------------------下面是曾经用过的截取第三个的字符串的------------------------------*/
// $name1 = mysql_result($my_rst,0,"name");
// $name = preg_match("/([1-9][0-9]+)/",$name1,$r);
// $name = $r[0];
// if($name == ""){
// $name=preg_replace('#^(?:[\x00-\x7F]|[\xC0-\xFF][\x80-\xBF]+){0,2}'.
// '((?:[\x00-\x7F]|[\xC0-\xFF][\x80-\xBF]+){0,1}).*#s',
// '$1',$name1);
// }
/*--------------------------------------------第四种方法(UTF-8)---------------------------------------------*/
function cut_str($sourcestr, $cutlength)
{
$returnstr = '';
$i = 0;
$n = 0;
$str_length = strlen($sourcestr);//字符串的字节数
while ($n $cutlength $i = $str_length) {
$temp_str = substr($sourcestr, $i, 1);
$ascnum = ord($temp_str);//得到字符串中第$i位字符的ASCII码
if ($ascnum >= 224) {
$returnstr = $returnstr . substr($sourcestr, $i, 3);//根据UTF-8编码规范，将3个连续的字符计为单个字符
$i = $i + 3;//实际Byte记为3
$n++;//字串长度为1
} elseif ($ascnum >= 192)//如果ASCII位高于192
{
$returnstr = $returnstr . substr($sourcestr, $i, 2);//根据UTF-8编码规范，将2个连续的字符记为单个字符
$i = $i + 2;//实际Byte记为2
$n++;//字串长度为1
} elseif ($ascnum >= 65 $ascnum = 90)//如果是大写字母
{
$returnstr = $returnstr . substr($sourcestr, $i, 1);
$i = $i + 1;//byte记为1
$n++;//但考虑到整体美观，大写字母计成一个高位字符
} else {
$returnstr = $returnstr . substr($sourcestr, $i, 1);
$i = $i + 1;//实际的Byte记为1
$n = $n + 0.5;//小写字母和半角标点等与半个高位字符宽...
}
}
if ($str_length > $cutlength) {
$returnstr = $returnstr . "...";//超过长度时在尾处加上省略号
}
return $returnstr;
}
/*--------------------第五种方法（UTF-8）---------------------------------------------*/
function FSubstr($title, $start, $len = "", $magic = true)
{
if ($len == "") $len = strlen($title);
if ($start != 0) {
$startv = ord(substr($title, $start, 1));
if ($startv >= 128) {
if ($startv 192) {
for ($i = $start - 1; $i > 0; $i--) {
$tempv = ord(substr($title, $i, 1));
if ($tempv >= 192) break;
}
$start = $i;
}
}
}
if (strlen($title) = $len) return substr($title, $start, $len);
$alen = 0;
$blen = 0;
$realnum = 0;
$length = 0;
for ($i = $start; $i strlen($title); $i++) {
$ctype = 0;
$cstep = 0;
$cur = substr($title, $i, 1);
if ($cur == "") {
if (substr($title, $i, 4) == "lt;") {
$cstep = 4;
$length += 4;
$i += 3;
$realnum++;
if ($magic) {
$alen++;
}
} elseif (substr($title, $i, 4) == "gt;") {
$cstep = 4;
$length += 4;
$i += 3;
$realnum++;
if ($magic) {
$alen++;
}
} elseif (substr($title, $i, 5) == "") {
$cstep = 5;
$length += 5;
$i += 4;
$realnum++;
if ($magic) {
$alen++;
}
} elseif (substr($title, $i, 6) == "quot;") {
$cstep = 6;
$length += 6;
$i += 5;
$realnum++;
if ($magic) {
$alen++;
}
} elseif (preg_match("/#(\d+);?/i", substr($title, $i), $match)) {
$cstep = strlen($match[0]);
$length += strlen($match[0]);
$i += strlen($match[0]) - 1;
$realnum++;
if ($magic) {
$blen++;
$ctype = 1;
}
}
} else {
if (ord($cur) >= 252) {
$cstep = 6;
$length += 6;
$i += 5;
$realnum++;
if ($magic) {
$blen++;
$ctype = 1;
}
} elseif (ord($cur) >= 248) {
$cstep = 5;
$length += 5;
$i += 4;
$realnum++;
if ($magic) {
$ctype = 1;
$blen++;
}
} elseif (ord($cur) >= 240) {
$cstep = 4;
$length += 4;
$i += 3;
$realnum++;
if ($magic) {
$blen++;
$ctype = 1;
}
} elseif (ord($cur) >= 224) {
$cstep = 3;
$length += 3;
$i += 2;
$realnum++;
if ($magic) {
$ctype = 1;
$blen++;
}
} elseif (ord($cur) >= 192) {
$ctype = 2;
$length += 2;
$i += 1;
$realnum++;
if ($magic) {
$blen++;
$ctype = 1;
}
} elseif (ord($cur) >= 128) {
$length += 1;
} else {
$cstep = 1;
$length += 1;
$realnum++;
if ($magic) {
if (ord($cur) >= 65 ord($cur) = 90) {
$blen++;
} else {
$alen++;
}
}
}
}
if ($magic) {
if (($blen * 2 + $alen) == ($len * 2)) break;
if (($blen * 2 + $alen) == ($len * 2) + 1) {
if ($ctype == 1) {
$length -= $cstep;
break;
} else {
break;
}
}
} else {
if ($realnum == $len) break;
}
}
unset($cur);
unset($alen);
unset($blen);
unset($realnum);
unset($ctype);
unset($cstep);
return substr($title, $start, $length);
}
function utf8Substr($str, $from, $len)
{
return preg_replace('#^(?:[\x00-\x7F]|[\xC0-\xFF][\x80-\xBF]+){0,' . $from . '}' .
'((?:[\x00-\x7F]|[\xC0-\xFF][\x80-\xBF]+){0,' . $len . '}).*#s',
'$1', $str);
}
$title = "你哈珀niad1纳斯达wop asdni你爱谁都没阿斯顿撒旦12ccs- sd";
$title = utf8Substr($title, 0, 15);
echo $title;
?>
更多关于PHP相关内容感兴趣的读者可查看本站专题：《PHP编码与转码操作技巧汇总》、《PHP数组(Array)操作技巧大全》、《php字符串(string)用法总结》、《php常用函数与技巧总结》及《PHP错误与异常处理方法总结》
