html实体分为alpha entities(named entities)和numeric entities,php函数htmlspecialchars、htmlentities都只能转化为alpha entities,如果要转化为numeric entities要使用mb_encode_numericentity函数,如转化为GBK编码的numeric entities:
$str="(王贯)'<";
$convmap=array(0x0,0xffff,0,0xffff);
$str=mb_encode_numericentity($str, $convmap,'gbk');
输出:(??疮)'<
更新:
Numeric Character Reference (简称:NCR):<
Character entities references :<
十进制的65279(16进制的0xFEFF) 是Unicode编码中的传输控制字符