php5.2 Json cannot correctly handle Chinese and GB encoding solutions_PHP tutorial

/*

In order to use json correctly, first we should use utf8 encoding for encoding, and then slightly process the return result of json_encode to get the correct result .
I wrote a simple class to wrap these two functions,
**/
class Json{
public static function encode($str){
$code = json_encode($str);
return preg_replace("#\u([0-9a-f]+)#ie", "iconv('UCS-2', 'UTF-8', pack('H4' , '\1'))", $code);
}

public static function decode($str){
return json_decode($str);
}
}
//When used

Json::encode($code);
Json::decode($code);
/**This can correctly handle utf8 encoded Chinese.

PS: For GB-encoded Chinese, we can first convert to UTF8 encoding when encoding, then encode, and then perform a utf8 -> gb conversion when decoding.
In addition, we generally return the results of json_encode to the client for use. We can actually use the unescape function of JavaScript to decode the unicode-encoded Chinese and restore it to the correct Chinese.

Or use: $title = mb_convert_encoding($title, 'HTML-ENTITIES', $this->_outCharset);//It will be displayed normally in any encoding
********/