今天项目升级到php5.4，gbk编码，htmlspecialchars转换后的字符串为空，郁闷啊
解决，加上编码吧，这么多地方用到htmlspecialchars，改起来真麻烦，看来以后得自己封装一下了。
UPGRADING说到
[html]
- the default character set for htmlspecialchars() and htmlentities() is
now UTF-8. In previous versions it was ISO-8859-1. Note that changing
your output charset via the php.ini default_charset directive does not
affect htmlspecialchars/htmlentities unless you are passing "" (an
empty string) as the encoding parameter to your htmlspecialchars/htmlentities
calls.
手册中也说到
[html]
string htmlspecialchars ( string $string [, int $flags = ENT_COMPAT | ENT_HTML401 [, string $encoding = 'UTF-8' [, bool $double_encode = true ]]] )
[html]
Defines encoding used in conversion. If omitted, the default value for this argument is ISO-8859-1 in versions of PHP prior to 5.4.0, and UTF-8 from PHP 5.4.0 onwards.
