php过滤非法字符类

<?php   class sqlsafe {       private $getfilter = "'|(and|or)\\b.+?(>|<|=|in|like)|\\/\\*.+?\\*\\/|<\\s*script\\b|\\bEXEC\\b|UNION.+?SELECT|UPDATE.+?SET|INSERT\\s+INTO.+?VALUES|(SELECT|DELETE).+?FROM|(CREATE|ALTER|DROP|TRUNCATE)\\s+(TABLE|DATABASE)";       private $postfilter = "\\b(and|or)\\b.{1,6}?(=|>|<|\\bin\\b|\\blike\\b)|\\/\\*.+?\\*\\/|<\\s*script\\b|\\bEXEC\\b|UNION.+?SELECT|UPDATE.+?SET|INSERT\\s+INTO.+?VALUES|(SELECT|DELETE).+?FROM|(CREATE|ALTER|DROP|TRUNCATE)\\s+(TABLE|DATABASE)";      private $cookiefilter = "\\b(and|or)\\b.{1,6}?(=|>|<|\\bin\\b|\\blike\\b)|\\/\\*.+?\\*\\/|<\\s*script\\b|\\bEXEC\\b|UNION.+?SELECT|UPDATE.+?SET|INSERT\\s+INTO.+?VALUES|(SELECT|DELETE).+?FROM|(CREATE|ALTER|DROP|TRUNCATE)\\s+(TABLE|DATABASE)";       /**        * 构造函数       */      public function __construct() {           foreach($_GET as $key=>$value){$this->stopattack($key,$value,$this->getfilter);}          foreach($_POST as $key=>$value){$this->stopattack($key,$value,$this->postfilter);}           foreach($_COOKIE as $key=>$value){$this->stopattack($key,$value,$this->cookiefilter);}       }       /**        * 参数检查并写日志        */      public function stopattack($StrFiltKey, $StrFiltValue, $ArrFiltReq){           if(is_array($StrFiltValue))$StrFiltValue = implode($StrFiltValue);           if (preg_match("/".$ArrFiltReq."/is",$StrFiltValue) == 1){                  $this->writeslog($_SERVER["REMOTE_ADDR"]."    ".strftime("%Y-%m-%d %H:%M:%S")."    ".$_SERVER["PHP_SELF"]."    ".$_SERVER["REQUEST_METHOD"]."    ".$StrFiltKey."    ".$StrFiltValue);               showmsg('您提交的参数非法,系统已记录您的本次操作！','',0,1);           }       }       /**        * SQL注入日志        */      public function writeslog($log){           $log_path = CACHE_PATH.'logs'.DIRECTORY_SEPARATOR.'sql_log.txt';           $ts = fopen($log_path,"a+");           fputs($ts,$log."\r\n");           fclose($ts);       }   }   ?>