sql注入基础过滤

/**
     * sql注入过滤
     * @param $string 需要校验的字符
     * @param $type get post cookie
     */
    public function sqlFilter($string,$type){
        $getfilter="/^'|(and|or)\\b.+?(>|<|=|in|like)|\\/\\*.+?\\*\\/|<\\s*script\\b|\\bEXEC\\b|UNION.+?SELECT|UPDATE.+?SET|INSERT\\s+INTO.+?VALUES|(SELECT|DELETE).+?FROM|(CREATE|ALTER|DROP|TRUNCATE)\\s+(TABLE|DATABASE)$/i";
        $postfilter="/^\\b(and|or)\\b.{1,6}?(=|>|<|\\bin\\b|\\blike\\b)|\\/\\*.+?\\*\\/|<\\s*script\\b|\\bEXEC\\b|UNION.+?SELECT|UPDATE.+?SET|INSERT\\s+INTO.+?VALUES|(SELECT|DELETE).+?FROM|(CREATE|ALTER|DROP|TRUNCATE)\\s+(TABLE|DATABASE)$/i";
        $cookiefilter="/^\\b(and|or)\\b.{1,6}?(=|>|<|\\bin\\b|\\blike\\b)|\\/\\*.+?\\*\\/|<\\s*script\\b|\\bEXEC\\b|UNION.+?SELECT|UPDATE.+?SET|INSERT\\s+INTO.+?VALUES|(SELECT|DELETE).+?FROM|(CREATE|ALTER|DROP|TRUNCATE)\\s+(TABLE|DATABASE)$/i";
        switch($type){
            case 'post':
                if(preg_match($postfilter,$string)){
                    die(json_encode(array('msg'=>'data valid')));
                }
                break;
            case 'get':
                if(preg_match($getfilter,$string)){
                    die(json_encode(array('msg'=>'data valid')));
                }
                break;
            case 'cookie':
                if(preg_match($cookiefilter,$string)){
                    die(json_encode(array('msg'=>'data valid')));
                }
                break;
        }
        if (!get_magic_quotes_gpc()) {
            $string = stripslashes($string);
        }
        //      $string = mysql_real_escape_string ($string); //\x00 \n \r \' " \x1a
        $string = addslashes($string);
        $string = nl2br($string); // 回车转换
        $string= htmlspecialchars($string); // html标记转换
        return $string;
    }