Intercepting strings Code summary for intercepting Chinese strings in PHP

String interception is a very common programming task, and string interception with Chinese characters is often used. Although it is not difficult, writing the function yourself is time-consuming. Here is a relatively easy-to-use string interception function that can meet the basic needs.
1. Intercept GB2312 Chinese string

Copy code The code is as follows:

< ?php
//Intercept Chinese string
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. Intercept utf8 encoded multi-byte string

Copy code The code is as follows:

< ?php
//Intercept utf8 string
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. Chinese character interception function supported by UTF-8 and GB2312

Copy code The code is as follows:

< ?php
/*
Utf-8 and gb2312 are both Supported Chinese character interception functions
cut_str(string, interception length, start length, encoding);
Encoding defaults to utf-8
Start length defaults to 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;
}
}
$str = "abcd needs to intercept the string";
echo cut_str($str, 8, 0, 'gb2312');
?>

4. BugFree's character interception function

Copy the code The code is as follows:

< ?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 = "17test.info is at the forefront of automated testing in China";
$Length = "18";
$Append = false;
echo sysSubStr($String,$Length,$Append);
?> ;

The above has introduced a summary of the code for intercepting Chinese strings in PHP, including the content of intercepting strings. I hope it will be helpful to friends who are interested in PHP tutorials.