php防禦XSS攻擊

php防御XSS攻击，使用方法和详情看 http://www.tongqiong.com/read.php?tid-474.html

function remove_xss($val) {
   // remove all non-printable characters. CR(0a) and LF(0b) and TAB(9) are allowed
   // this prevents some character re-spacing such as