php 截取中文_[PHP教程]

< ?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');
?>

4. BugFree 的字符截取函数
< ?php
/**
* @package BugFree
* @version Id: FunctionsMain.inc.php,v 1.32 2005/09/24 11:38:37 wwccss Exp
*
*
* Return part of a string(Enhance the function substr())
*
* @author Chunsheng Wang
* @param string String the string to cut.
* @param int Length the length of returned string.
* @param booble Append whether append "...": false|true
* @return string the cutted string.
*/
function sysSubStr(String,Length,Append = false)
{
if (strlen(String) < = Length )
{
return String;
}
else
{
I = 0;
while (I < Length)
{
StringTMP = substr(String,I,1);
if ( ord(StringTMP) >=224 )
{
StringTMP = substr(String,I,3);
I = I + 3;
}
elseif( ord(StringTMP) >=192 )
{
StringTMP = substr(String,I,2);
I = I + 2;
}
else
{
I = I + 1;
}
StringLast[] = StringTMP;
}
StringLast = implode("",StringLast);
if(Append)
{
StringLast .= "...";
}
return StringLast;
}
}

String = "CodeBit.cn -- 简单、精彩、通用";
Length = "18";
Append = false;
echo sysSubStr(String,Length,Append);
?>