PHP截取字符串<br />
PHP截取字符串，用函数截取字符串的专题，支持UTF-8、GB2312、GBK多种字符集。<br />
截取GB2312中文字符串<br />
<?php<br />
//截取中文字符串<br />
function mysubstr($str, $start, $len) {<br />
$tmpstr = "";<br />
$strlen = $start + $len;<br />
for($i = 0; $i < $strlen; $i++) {<br />
if(ord(substr($str, $i, 1)) > 0xa0) {<br />
$tmpstr .= substr($str, $i, 2);<br />
$i++;<br />
} else<br />
$tmpstr .= substr($str, $i, 1);<br />
}<br />
return $tmpstr;<br />
}<br />
?><br />
<br />
截取utf8编码的多字节字符串 <br />
<?php<br />
//截取utf8字符串<br />
function utf8Substr($str, $from, $len)<br />
{<br />
return preg_replace(#^(?:[\x00-\x7F]|[\xC0-\xFF][\x80-\xBF]+){0,.$from.}.<br />
((?:[\x00-\x7F]|[\xC0-\xFF][\x80-\xBF]+){0,.$len.}).*#s,<br />
$1,$str);<br />
}<br />
?><br />
<br />
UTF-8、GB2312都支持的汉字截取函数<br />
<?php<br />
/* <br />
Utf-8、gb2312都支持的汉字截取函数 <br />
cut_str(字符串, 截取长度, 开始长度, 编码); <br />
编码默认为 utf-8 <br />
开始长度默认为 0 <br />
*/ <br />
<br />
function cut_str($string, $sublen, $start = 0, $code = UTF-8) <br />
{ <br />
if($code == UTF-8) <br />
{ <br />
$pa = "/[\x01-\x7f]|[\xc2-\xdf][\x80-\xbf]|\xe0[\xa0-\xbf][\x80-\xbf]|[\xe1-\xef][\x80-\xbf][\x80-\xbf]|\xf0[\x90-\xbf][\x80-\xbf][\x80-\xbf]|[\xf1-\xf7][\x80-\xbf][\x80-\xbf][\x80-\xbf]/"; <br />
preg_match_all($pa, $string, $t_string); <br />
<br />
if(count($t_string[0]) - $start > $sublen) return join(, array_slice($t_string[0], $start, $sublen))."..."; <br />
return join(, array_slice($t_string[0], $start, $sublen)); <br />
} <br />
else <br />
{ <br />
$start = $start*2; <br />
$sublen = $sublen*2; <br />
$strlen = strlen($string); <br />
$tmpstr = ; <br />
<br />
for($i=0; $i< $strlen; $i++) <br />
{ <br />
if($i>=$start && $i< ($start+$sublen)) <br />
{ <br />
if(ord(substr($string, $i, 1))>129) <br />
{ <br />
$tmpstr.= substr($string, $i, 2); <br />
} <br />
else <br />
{ <br />
$tmpstr.= substr($string, $i, 1); <br />
} <br />
} <br />
if(ord(substr($string, $i, 1))>129) $i++; <br />
} <br />
if(strlen($tmpstr)< $strlen ) $tmpstr.= "..."; <br />
return $tmpstr; <br />
} <br />
} <br />
<br />
$str = "abcd需要截取的字符串"; <br />
echo cut_str($str, 8, 0, gb2312); <br />
?><br />
<br />
PHP字符截取函数<br />
<?php<br />
function sysSubStr($String,$Length,$Append = false) <br />
{ <br />
if (strlen($String) < = $Length ) <br />
{ <br />
return $String; <br />
} <br />
else <br />
{ <br />
$I = 0; <br />
while ($I < $Length) <br />
{ <br />
$StringTMP = substr($String,$I,1); <br />
if ( ord($StringTMP) >=224 ) <br />
{ <br />
$StringTMP = substr($String,$I,3); <br />
$I = $I + 3; <br />
} <br />
elseif( ord($StringTMP) >=192 ) <br />
{ <br />
$StringTMP = substr($String,$I,2); <br />
$I = $I + 2; <br />
} <br />
else <br />
{ <br />
$I = $I + 1; <br />
} <br />
$StringLast[] = $StringTMP; <br />
} <br />
$StringLast = implode("",$StringLast); <br />
if($Append) <br />
{ <br />
$StringLast .= "..."; <br />
} <br />
return $StringLast; <br />
} <br />
} <br />
<br />
$String = " 简单、精彩、通用"; <br />
$Length = "18"; <br />
$Append = false; <br />
echo sysSubStr($String,$Length,$Append); <br />
?><br />