最近不是在折腾论坛嘛，各种类各种函数，原创一些，从别人那儿qiang过来一些，在此分享出来，希望有朋友能用的到~

注意：部分函数可能不够完善，由此造成的漏洞风险自担~

提交过滤

function filter($text){ //完全过滤注释 $text = preg_replace("/<!--?.*-->/", "", $text); //完全过滤js $text = preg_replace("/<script?.*/script>/", "", $text); //过滤危险的属性，如：过滤on事件lang js while (preg_match("/(<[^><]+)( lang|action|background|codebase|dynsrc|lowsrc)[^><]+/i", $text, $mat)) { $text = str_replace($mat[0], $mat[1], $text); } while (preg_match("/(<[^><]+)(window.|javascript:|js:|about:|file:|document.|vbs:|cookie)([^><]*)/i", $text, $mat)) { $text = str_replace($mat[0], $mat[1] . $mat[3], $text); } //过滤多余html $text = preg_replace("/</?(html|head|meta|link|base|basefont|body|bgsound|script|form|iframe|frame|frameset|applet|id|ilayer|layer|name|script|xml)[^><]*>/i", "", $text); //反转换 $text = str_replace("[", "<", $text); $text = str_replace("]", ">", $text); $text = str_replace("|", """, $text); return $text;}

提交过滤2

function stripslashes_array(&$array){ while (list($key, $var) = each($array)) { if ($key != "argc" && $key != "argv" && (strtoupper($key) != $key || "" . intval($key) == "$key")) { if (is_string($var)) { $array[$key] = stripslashes($var); } if (is_array($var)) { $array[$key] = stripslashes_array($var); } } } return $array;}

字符串截取（这个是emlog里提出来的，其实也就是substr的增强版）

function subString($strings, $start, $length){ if (function_exists("mb_substr") && function_exists("mb_strlen")) { $sub_str = mb_substr($strings, $start, $length, "utf8"); return mb_strlen($sub_str, "utf8") < mb_strlen($strings, "utf8") ? $sub_str . "..." : $sub_str; } $str = substr($strings, $start, $length); $char = 0; for ($i = 0; $i < strlen($str); $i++) { if (ord($str[$i]) >= 128) $char++; } $str2 = substr($strings, $start, $length + 1); $str3 = substr($strings, $start, $length + 2); if ($char % 3 == 1) { if ($length <= strlen($strings)) { $str3 = $str3 .= "..."; } return $str3; } if ($char % 3 == 2) { if ($length <= strlen($strings)) { $str2 = $str2 .= "..."; } return $str2; } if ($char % 3 == 0) { if ($length <= strlen($strings)) { $str = $str .= "..."; } return $str; }}

IP地址匿名化（最后一位替换为星号）

function AnonymousIP() { $ip = GetIP(); if ($ip == "Unknown") { $removed_ip = "未知用户"; } if (strpos($ip, ":")) { $removed_ip = "IPv6用户"; } else { $reg1 = "/((?:d+.){3})d+/"; $reg2 = "~(d+).(d+).(d+).(d+)~"; $removed_ip = preg_replace($reg1, "\1*", $ip); } return $removed_ip;}

获取客户端IP地址

function GetIP(){ if (@$_SERVER["HTTP_X_FORWARDED_FOR"]) $ip = $_SERVER["HTTP_X_FORWARDED_FOR"]; else if (@$_SERVER["HTTP_CLIENT_IP"]) $ip = $_SERVER["HTTP_CLIENT_IP"]; else if (@$_SERVER["REMOTE_ADDR"]) $ip = $_SERVER["REMOTE_ADDR"]; else if (@getenv("HTTP_X_FORWARDED_FOR")) $ip = getenv("HTTP_X_FORWARDED_FOR"); else if (@getenv("HTTP_CLIENT_IP")) $ip = getenv("HTTP_CLIENT_IP"); else if (@getenv("REMOTE_ADDR")) $ip = getenv("REMOTE_ADDR"); else $ip = "Unknown"; return $ip;}

字符串加密（支持中文）

function dencrypt($string, $isEncrypt = true, $key = "youdian"){ if (!isset($string{0}) || !isset($key{0})) { return false; }  $dynKey = $isEncrypt ? hash("sha1", microtime(true)) : substr($string, 0, 40); $fixedKey = hash("sha1", $key);  $dynKeyPart1 = substr($dynKey, 0, 20); $dynKeyPart2 = substr($dynKey, 20); $fixedKeyPart1 = substr($fixedKey, 0, 20); $fixedKeyPart2 = substr($fixedKey, 20); $key = hash("sha1", $dynKeyPart1 . $fixedKeyPart1 . $dynKeyPart2 . $fixedKeyPart2);  $string = $isEncrypt ? $fixedKeyPart1 . $string . $dynKeyPart2 : (isset($string{339}) ? gzuncompress(base64_decode(substr($string, 40))) : base64_decode(substr($string, 40)));  $n = 0; $result = ""; $len = strlen($string);  for ($n = 0; $n < $len; $n++) { $result .= chr(ord($string{$n}) ^ ord($key{$n % 40})); } return $isEncrypt ? $dynKey . str_replace("=", "", base64_encode($n > 299 ? gzcompress($result) : $result)) : substr($result, 20, -20);}

检查字符串是否包含中文

function CheckChinese($string){ if (preg_match("/[x7f-xff]/", $string)) { return true; } else { return false; }}

隐藏文件真实路径

function FileHeaderJump($file){ header("Content-Description: File Transfer"); header("Content-Type: application/octet-stream"); header("Content-Disposition: attachment; filename=" . basename($file)); header("Content-Transfer-Encoding: binary"); header("Expires: 0"); header("Cache-Control: must-revalidate, post-check=0, pre-check=0"); header("Pragma: public"); header("Content-Length: " . filesize($file)); ob_clean(); flush(); readfile($file); exit;}

生成随机字符串，自定义长度

function CreateRandomString($length){ $chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"; $password = ""; for ($i = 0; $i < $length; $i++) { $password .= $chars[mt_rand(0, strlen($chars) - 1)]; } return $password;}