php中截取字符串函数
本文章是收集了几个常用的字符串截取函数,这是解决了php中对各种编码的字符截取会乱码的问题,有需要的同学可以参考一下.
1、截取GB2312中文字符串,代码如下:
<?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,代码如下:
<?php //截取utf8字符串 function utf8Substr( $str , $from , $len ) //开源代码phpfensi测试数据 { 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,代码如下:
<?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 <wwccss@263.net> * @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 = "phpfensi测试数据-- 简单、精彩、通用" ; $Length = "18" ; $Append = false; echo sysSubStr( $String , $Length , $Append ); ?>查看更多关于php中截取字符串函数 - php函数的详细内容...
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