PHP 中文处理

一、编码范围
1. GBK (GB2312/GB18030)
\x00-\xff GBK双字节编码范围
\x20-\x7f ASCII
\xa1-\xff 中文
\x80-\xff 中文

2. UTF-8 (Unicode)
\u4e00-\u9fa5 (中文)
\x3130-\x318F (韩文
\xAC00-\xD7A3 (韩文)
\u0800-\u4e00 (日文)
ps: 韩文是大于[\u9fa5]的字符

正则例子:

//判断内容里有没有中文-GBK (PHP)function check_is_chinese($s){return preg_match('/[\x80-\xff]./', $s);} //获取字符串长度-GBK (PHP)function gb_strlen($str){$count = 0;for($i=0; $i<strlen($str); $i++){$s = substr($str, $i, 1);if (preg_match("/[\x80-\xff]/", $s)) ++$i;++$count;}return $count;} //截取字符串字串-GBK (PHP)function gb_substr($str, $len){$count = 0;for($i=0; $i<strlen($str); $i++){if($count == $len) break;if(preg_match("/[\x80-\xff]/", substr($str, $i, 1))) ++$i;++$count;}return substr($str, 0, $i);} //统计字符串长度-UTF8 (PHP)function utf8_strlen($str) {$count = 0;for($i = 0; $i <strlen($str); $i++){$value = ord($str[$i]);if($value> 127) {$count++;if($value>= 192 && $value <= 223) $i++;elseif($value>= 224 && $value <= 239) $i = $i + 2; elseif($value>= 240 && $value <= 247) $i = $i + 3;else die('Not a UTF-8 compatible string');}$count++;}return $count;}  //截取字符串-UTF8(PHP)function utf8_substr($str,$position,$length){$start_position = strlen($str);$start_byte = 0;$end_position = strlen($str);$count = 0;for($i = 0; $i <strlen($str); $i++){if($count>= $position && $start_position> $i){$start_position = $i;$start_byte = $count;}if(($count-$start_byte)>=$length) {$end_position = $i;break;}$value = ord($str[$i]);if($value> 127){$count++;if($value>= 192 && $value <= 223) $i++;elseif($value>= 224 && $value <= 239) $i = $i + 2;elseif($value>= 240 && $value <= 247) $i = $i + 3;else die('Not a UTF-8 compatible string');}$count++; }return(substr($str,$start_position,$end_position-$start_position)); }  //字符串长度统计-UTF8 [中文3个字节，俄文、韩文占2个字节，字母占1个字节] (Ruby)def utf8_string_length(str)temp = CGI::unescape(str)i = 0;j = 0;temp.length.times{|t|if temp[t] <127i += 1elseif temp[t]>= 127 and temp[t] <224j += 1if 0 == (j % 2)i += 2j = 0endelsej += 1if 0 == (j % 3)i +=2j = 0endend}return i} //判断是否是有韩文-UTF-8 (JavaScript)function checkKoreaChar(str) {for(i=0; i<str.length; i++) {if(((str.charCodeAt(i)> 0x3130 && str.charCodeAt(i) <0x318F) || (str.charCodeAt(i)>= 0xAC00 && str.charCodeAt(i) <= 0xD7A3))) {return true;}}return false;}//判断是否有中文字符-GBK (javascript)function check_chinese_char(s){return (s.length != s.replace(/[^\x00-\xff]/g,"**").length);}