1. 截取GB2312中文字符串
<?php
//截取中文字符串
function
mysubstr($str, $start, $len) {
$tmpstr = "";
$strlen = $start + $len;
for($i = 0; $i < $strlen; $i++) {
if(ord(substr($str, $i, 1)) >
0xa0) {
$tmpstr .= substr($str, $i, 2);
$i++;
} else
$tmpstr .=
substr($str, $i, 1);
}
return $tmpstr;
}
?>
2. 截取utf8编码的多字节字符串
<?php
//截取utf8字符串
function utf8Substr($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);
}
?>
3. UTF-8、GB2312都支持的汉字截取函数
<?php
/*
Utf-8、gb2312都支持的汉字截取函数
cut_str(字符串,
截取长度, 开始长度, 编码);
编码默认为 utf-8 开始长度默认为 0
*/
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;
}
}
$str = "abcd需要截取的字符串";
echo cut_str($str, 8, 0, 'gb2312');
?>
