因为对编码不熟悉，在处理起一些编码问题来，经常搞得抓耳挠腮的，最近在PHPChina中发现了一个高人写的类。可以完成一下转换

Charset::convert(string input,string incharset,string outcharset)

Charset::unescape(string escaped,string outcharset)

Charset::escape(string string,string incharset)

Charset::jsondecode(string encoded,string outcharset)

Charset::jsonencode(mix value,string incharset)

Charset::pinYin(string chinese,string incharset)

PHP代码

<?php
/*
* 编码转换
* 说明:
* jsonencode 有参考Services_JSON 但有很大区别 此处可以将utf-8 gb2312 big5都可以jsonencode
* jsondecode 自己原创 该算法是模拟目录读取的方法
* 可以将json中中文unicode编码unescape为gbk big5 utf8
*/
define(‘TABLE_DIR’,’./table’);
define(‘USEEXISTS’,FALSE);//是否使用系统存在的php内置编码转换函数
//其实php内置编码转换函数转换的不够好
class Charset{

private static $target_lang,$source_lang;
protected static $string = ”;
protected static $table = NULL;

PHP代码
/**
* 编码互换
*
* @param string $source
* @param string $source_lang 输入编码 ‘utf-8’ or ‘gb2312’ or ‘big5’
* @param string $target_lang 输出编码 ‘utf-8’ or ‘gb2312’ or ‘big5’
* @return string
*/
static public function convert($source,$source_lang,$target_lang=’utf-8′){
if($source_lang != ”){
$source_lang = str_replace(
array(‘gbk’,’utf8′,’big-5′),
array(‘gb2312′,’utf-8′,’big5’),
strtolower($source_lang)
);
}
if($target_lang != ”){
$target_lang = str_replace(
array(‘gbk’,’utf8′,’big-5′),
array(‘gb2312′,’utf-8′,’big5’),
strtolower($target_lang)
);
}
if($source_lang == $target_lang||$source == ”){
return $source;
}
$index = $source_lang.”_”.$target_lang;
if(USEEXISTS&&!in_array($index,array(‘gb2312_big5′,’big5_gb2312’))){//繁简互换并不是交换字符集编码
if(function_exists(‘iconv’)){
return iconv($source_lang,$target_lang,$source);
}
if(function_exists(‘mb_convert_encoding’)){
return mb_convert_encoding($source,$target_lang,$source_lang);
}
}
$table = self::loadtable($index);
if(!$table){
return $source;
}
self::$string = $source;
self::$source_lang = $source_lang;
self::$target_lang = $target_lang;
if($source_lang==’gb2312’||$source_lang==’big5′){
if($target_lang==’utf-8′){
self::$table = $table;
return self::CHS2UTF8();
}
if($target_lang==’gb2312′){
self::$table = array_flip($table);
}else{
self::$table = $table;
}
return self::BIG2GB();
}elseif(self::$source_lang==’utf-8′){
self::$table = array_flip($table);
return self::UTF82CHS();
}
return NULL;
}

PHP代码
/**
* js 中的unescape功能
*
* @param string $str 源字符串
* @param string $charset 目标字符串编码 ‘utf-8’ or ‘gb2312’ or ‘big5’
* @return string
*/
static public function unescape($str,$charset=’utf-8′){
$charset = strtolower($charset);
self::$target_lang = str_replace(
array(‘gbk’,’utf8′,’big-5′),
array(‘gb2312′,’utf-8′,’big5’),
$charset
);
if(self::$target_lang!=’utf-8’&&
!(USEEXISTS&&(function_exists(‘mb_convert_encoding’)||function_exists(‘iconv’)))
){
self::$table = array_flip(self::loadtable(‘unescapeto’.$charset));
}
return preg_replace_callback(‘/[\\|%]u(w{4})/iU’,array(‘Charset’,’descape’),$str);
}

PHP代码
/**
* js 中的escape功能
*
* @param string $str 源字符串
* @param string $charset 源字符串编码 ‘utf-8’ or ‘gb2312’ or ‘big5’
* @return string
*/
static public function escape($str,$charset=’utf-8′){
$escaped = ”;
$charset = strtolower($charset);
$charset = str_replace(
array(‘gbk’,’big-5′,’utf8′),
array(‘gb2312′,’big5′,’utf-8’),
$charset
);
$ulen = strlen($str);
if($charset!=’utf-8′){
$table = self::loadtable($charset.’escape’);
for($i=0;$i<$ulen;$i++){
$c = $str[$i];
if(ord($c)>0x80){
$bin = $c.$str[$i+1];
$i += 1;
$escaped .= sprintf(‘u%04X’,$table[hexdec(bin2hex($bin))]);
// bin2hex 返回的是string 必须再转化
}else{
$escaped .= $c;
}
}
return $escaped;
}else{
for($i=0;$i<$ulen;$i++){
$c = $str[$i];
$char = ord($c);
switch ($char>>4){
case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
$escaped .= $c;
break;
case 12: case 13:
$char = ((($char&0x1F)<<6)|(ord($str[++$i])&0x3F));
$escaped .= sprintf(‘u%04X’,$char);
break;
case 14:
$char = ((($char&0x0F)<<12)|((ord($str[++$i])&0x3F)<<6)|(ord($str[++$i])&0x3F));
$escaped .= sprintf(‘u%04X’,$char);
break;
default:$escaped .= $c;break;
}
/*$cb = decbin(ord($c));
if(strlen($cb)==8){
$csize = strpos(decbin(ord($cb)),”0″);
for($j=0;$j < $csize;$j++){
$i++;
$c .= $str[$i];
}
$escaped .= sprintf(‘u%04X’,self::utf82u($c));
}else{
$escaped .= $c;
}*/
}
return $escaped;
}
}

PHP代码
/**
* json_decode
*
* @param string $encoded 源字符串
* @param string $charset 目标字符串编码 ‘utf-8’ or ‘gb2312’ or ‘big5’
* @return string/array/boolean/null
*/
static public function jsondecode($encoded,$charset=’utf-8′){
$encoded = preg_replace(‘/([tbfnr ])*/s’,”,$encoded);//eat whitespace
self::$target_lang = $charset;
$c = self::cursor($encoded);
switch($c){
case ‘{‘:return self::parseArray($encoded);
case ‘[‘:return self::parseArray($encoded,FALSE);
case ‘”‘:return self::string_find($encoded);
case ‘t’:return TRUE;
case ‘f’:return FALSE;
case ‘n’:return NULL;
default:return self::num_read($c.$encoded);
}
}

PHP代码
/**
* json_encode
*
* @param mixvar $var 多类型变量
* @param string $charset 默认’utf-8’源变量中字符编码 ‘utf-8’ or ‘gb2312’ or ‘big5’
* @return string
*/
static public function jsonencode($var,$charset=NULL){
if(is_null($charset)){
$charset = self::$source_lang;
}else{
self::$source_lang = $charset;
}
if(!$charset){
$charset = ‘utf-8’;
}
switch (gettype($var)){
case ‘boolean’:
return $var ? ‘true’ : ‘false’;
case ‘NULL’:
return ‘null’;
case ‘integer’:
return (int) $var;
case ‘double’:
case ‘float’:
return (float) $var;
case ‘string’:
$var = strtr($var,array(“r” => ‘\r’,”n” => ‘\n’,”t” => ‘\t’,”b” => ‘\b’,
“f” => ‘\f’,’\’ => ‘\\’,'”‘ => ‘”‘,”x08″ => ‘b’,”x0c” => ‘f’)
);
$var = self::escape($var,$charset);
return ‘”‘.$var.'”‘;
case ‘array’:
return self::encodearray($var);
case ‘object’:
$var = get_object_vars($var);
return self::encodearray($var);
default:return ‘null’;
}
}