1. PHP encryption and decryption
PHP encryption and decryption functions can be used to encrypt some useful strings and store them in the database, and through reversible decryption of the strings, the The function uses base64 and MD5 encryption and decryption.
function encryptDecrypt($key, $string, $decrypt){ if($decrypt){ $decrypted = rtrim(mcrypt_decrypt(MCRYPT_RIJNDAEL_256, md5($key), base64_decode($string), MCRYPT_MODE_CBC, md5(md5($key))), "12"); return $decrypted; }else{ $encrypted = base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_256, md5($key), $string, MCRYPT_MODE_CBC, md5(md5($key)))); return $encrypted; } }
The usage method is as follows:
//以下是将字符串“Helloweba欢迎您”分别加密和解密 //加密: echo encryptDecrypt('password', 'Helloweba欢迎您',0); //解密: echo encryptDecrypt('password', 'z0JAx4qMwcF+db5TNbp/xwdUM84snRsXvvpXuaCa4Bk=',1);
2. PHP generates random strings
When we need to generate a random name, temporary password and other strings, we can use the following Function:
function generateRandomString($length = 10) { $characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'; $randomString = ''; for ($i = 0; $i < $length; $i++) { $randomString .= $characters[rand(0, strlen($characters) - 1)]; } return $randomString; }
The usage method is as follows:
echo generateRandomString(20);
3. PHP gets the file extension (suffix)
The following function can quickly get the file extension, that is, the suffix.
function getExtension($filename){ $myext = substr($filename, strrpos($filename, '.')); return str_replace('.','',$myext); }
The usage method is as follows:
$filename = '我的文档.doc'; echo getExtension($filename);
4. PHP gets the file size and formats it
The function used below can get the file size and convert it into KB that is easy to read. , MB and other formats.
function formatSize($size) { $sizes = array(" Bytes", " KB", " MB", " GB", " TB", " PB", " EB", " ZB", " YB"); if ($size == 0) { return('n/a'); } else { return (round($size/pow(1024, ($i = floor(log($size, 1024)))), 2) . $sizes[$i]); } }
The usage method is as follows:
$thefile = filesize('test_file.mp3'); echo formatSize($thefile);
5. PHP replace tag characters
Sometimes we need to replace strings and template tags with specified content, you can use the following Function:
function stringParser($string,$replacer){ $result = str_replace(array_keys($replacer), array_values($replacer),$string); return $result; }
The usage is as follows:
$string = 'The {b}anchor text{/b} is the {b}actual word{/b} or words used {br}to describe the link {br}itself'; $replace_array = array('{b}' => '<b>','{/b}' => '</b>','{br}' => '<br />'); echo stringParser($string,$replace_array);
6. PHP lists the file names in the directory
If you want to list all the files in the directory, use the following code That’s it:
function listDirFiles($DirPath){ if($dir = opendir($DirPath)){ while(($file = readdir($dir))!== false){ if(!is_dir($DirPath.$file)) { echo "filename: $file<br />"; } } } }
The usage is as follows:
listDirFiles('home/some_folder/');
7. PHP gets the URL of the current page
The following function can get the URL of the current page, whether it is http or https:
function curPageURL() { $pageURL = 'http'; if (!empty($_SERVER['HTTPS'])) {$pageURL .= "s";} $pageURL .= "://"; if ($_SERVER["SERVER_PORT"] != "80") { $pageURL .= $_SERVER["SERVER_NAME"].":".$_SERVER["SERVER_PORT"].$_SERVER["REQUEST_URI"]; } else { $pageURL .= $_SERVER["SERVER_NAME"].$_SERVER["REQUEST_URI"]; } return $pageURL; }
The usage method is as follows:
echo curPageURL();
8. PHP forced download of files
Sometimes we don’t want the browser to directly open files, such as PDF files, but to download files directly, Then the following function can force the file to be downloaded. The application/octet-stream header type is used in the function.
function download($filename){ if ((isset($filename))&&(file_exists($filename))){ header("Content-length: ".filesize($filename)); header('Content-Type: application/octet-stream'); header('Content-Disposition: attachment; filename="' . $filename . '"'); readfile("$filename"); } else { echo "Looks like file does not exist!"; } }
The usage method is as follows:
download('/down/test_45f73e852.zip');
9. PHP intercepts the string length
We often encounter situations where we need to intercept the length of a string (including Chinese characters), such as The title cannot exceed how many characters. The excess length is represented by.... The following function can meet your needs.
/* Utf-8、gb2312都支持的汉字截取函数 cut_str(字符串, 截取长度, 开始长度, 编码); 编码默认为 utf-8 开始长度默认为 0 */ function cutStr($string, $sublen, $start = 0, $code = 'UTF-8'){ if($code == 'UTF-8'){ $pa = "/[x01-x7f]|[xc2-xdf][x80-xbf]|xe0[xa0-xbf][x80-xbf]|[xe1-xef][x80-xbf][x80-xbf]|xf0[x90-xbf][x80-xbf][x80-xbf]|[xf1-xf7][x80-xbf][x80-xbf][x80-xbf]/"; preg_match_all($pa, $string, $t_string); if(count($t_string[0]) - $start > $sublen) return join('', array_slice($t_string[0], $start, $sublen))."..."; return join('', array_slice($t_string[0], $start, $sublen)); }else{ $start = $start*2; $sublen = $sublen*2; $strlen = strlen($string); $tmpstr = ''; for($i=0; $i<$strlen; $i++){ if($i>=$start && $i<($start+$sublen)){ if(ord(substr($string, $i, 1))>129){ $tmpstr.= substr($string, $i, 2); }else{ $tmpstr.= substr($string, $i, 1); } } if(ord(substr($string, $i, 1))>129) $i++; } if(strlen($tmpstr)<$strlen ) $tmpstr.= "..."; return $tmpstr; } }
The usage method is as follows:
$str = "jQuery插件实现的加载图片和页面效果"; echo cutStr($str,16);
10. PHP gets the real IP of the client
We often use the database to record the user’s IP. The following code can get the real IP of the client. IP:
//获取用户真实IP function getIp() { if (getenv("HTTP_CLIENT_IP") && strcasecmp(getenv("HTTP_CLIENT_IP"), "unknown")) $ip = getenv("HTTP_CLIENT_IP"); else if (getenv("HTTP_X_FORWARDED_FOR") && strcasecmp(getenv("HTTP_X_FORWARDED_FOR"), "unknown")) $ip = getenv("HTTP_X_FORWARDED_FOR"); else if (getenv("REMOTE_ADDR") && strcasecmp(getenv("REMOTE_ADDR"), "unknown")) $ip = getenv("REMOTE_ADDR"); else if (isset ($_SERVER['REMOTE_ADDR']) && $_SERVER['REMOTE_ADDR'] && strcasecmp($_SERVER['REMOTE_ADDR'], "unknown")) $ip = $_SERVER['REMOTE_ADDR']; else $ip = "unknown"; return ($ip); }
The usage method is as follows:
echo getIp();
11. PHP prevents SQL injection
When we query the database, for security reasons, we need to filter some illegal characters to prevent SQL For malicious injection, please take a look at the function:
function injCheck($sql_str) { $check = preg_match('/select|insert|update|delete|'|/*|*|../|./|union|into|load_file|outfile/', $sql_str); if ($check) { echo '非法字符!!'; exit; } else { return $sql_str; } }
The usage method is as follows:
echo injCheck('1 or 1=1');
12. PHP page prompts and jumps
When we perform form operations, sometimes in order to be friendly If you need to prompt the user for the operation result and jump to the relevant page, please see the following function:
function message($msgTitle,$message,$jumpUrl){ $str = '<!DOCTYPE HTML>'; $str .= '<html>'; $str .= '<head>'; $str .= '<meta charset="utf-8">'; $str .= '<title>页面提示</title>'; $str .= '<style type="text/css">'; $str .= '*{margin:0; padding:0}a{color:#369; text-decoration:none;}a:hover{text-decoration:underline}body{height:100%; font:12px/18px Tahoma, Arial, sans-serif; color:#424242; background:#fff}.message{width:450px; height:120px; margin:16% auto; border:1px solid #99b1c4; background:#ecf7fb}.message h3{height:28px; line-height:28px; background:#2c91c6; text-align:center; color:#fff; font-size:14px}.msg_txt{padding:10px; margin-top:8px}.msg_txt h4{line-height:26px; font-size:14px}.msg_txt h4.red{color:#f30}.msg_txt p{line-height:22px}'; $str .= '</style>'; $str .= '</head>'; $str .= '<body>'; $str .= '<p class="message">'; $str .= '<h3 id="msgTitle">'.$msgTitle.'</h3>'; $str .= '<p class="msg_txt">'; $str .= '<h4 id="message">'.$message.'</h4>'; $str .= '<p>系统将在 <span style="color:blue;font-weight:bold">3</span> 秒后自动跳转,如果不想等待,直接点击 <a href="{$jumpUrl}">这里</a> 跳转</p>'; $str .= "<script>setTimeout('location.replace('".$jumpUrl."')',2000)</script>"; $str .= '</p>'; $str .= '</p>'; $str .= '</body>'; $str .= '</html>'; echo $str; }
The usage is as follows:
message('操作提示','操作成功!','https://segmentfault.com/');
13. PHP calculation time
We are processing it time, it is necessary to calculate the length of time from the current time to a certain point in time. For example, to calculate the running time of the client, hh:mm:ss is usually used to represent
function changeTimeType($seconds) { if ($seconds > 3600) { $hours = intval($seconds / 3600); $minutes = $seconds % 3600; $time = $hours . ":" . gmstrftime('%M:%S', $minutes); } else { $time = gmstrftime('%H:%M:%S', $seconds); } return $time; }
The usage method is as follows:
$seconds = 3712; echo changeTimeType($seconds);
The following is Obtain client IP, string interception, download, etc. For details, please view the following code:
<?php/** * 获取客户端IP * @return [string] [description] */function getClientIp() { $ip = NULL; if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) { $arr = explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']); $pos = array_search('unknown',$arr); if(false !== $pos) unset($arr[$pos]); $ip = trim($arr[0]); }elseif (isset($_SERVER['HTTP_CLIENT_IP'])) { $ip = $_SERVER['HTTP_CLIENT_IP']; }elseif (isset($_SERVER['REMOTE_ADDR'])) { $ip = $_SERVER['REMOTE_ADDR']; } // IP地址合法验证 $ip = (false !== ip2long($ip)) ? $ip : '0.0.0.0'; return $ip; }/** * 获取在线IP * @return String */function getOnlineIp($format=0) { global $S_GLOBAL; if(empty($S_GLOBAL['onlineip'])) { if(getenv('HTTP_CLIENT_IP') && strcasecmp(getenv('HTTP_CLIENT_IP'), 'unknown')) { $onlineip = getenv('HTTP_CLIENT_IP'); } elseif(getenv('HTTP_X_FORWARDED_FOR') && strcasecmp(getenv('HTTP_X_FORWARDED_FOR'), 'unknown')) { $onlineip = getenv('HTTP_X_FORWARDED_FOR'); } elseif(getenv('REMOTE_ADDR') && strcasecmp(getenv('REMOTE_ADDR'), 'unknown')) { $onlineip = getenv('REMOTE_ADDR'); } elseif(isset($_SERVER['REMOTE_ADDR']) && $_SERVER['REMOTE_ADDR'] && strcasecmp($_SERVER['REMOTE_ADDR'], 'unknown')) { $onlineip = $_SERVER['REMOTE_ADDR']; } preg_match("/[\d\.]{7,15}/", $onlineip, $onlineipmatches); $S_GLOBAL['onlineip'] = $onlineipmatches[0] ? $onlineipmatches[0] : 'unknown'; } if($format) { $ips = explode('.', $S_GLOBAL['onlineip']); for($i=0;$i<3;$i++) { $ips[$i] = intval($ips[$i]); } return sprintf('%03d%03d%03d', $ips[0], $ips[1], $ips[2]); } else { return $S_GLOBAL['onlineip']; } }/** * 获取url * @return [type] [description] */function getUrl(){ $pageURL = 'http'; if (isset($_SERVER["HTTPS"]) && $_SERVER["HTTPS"] == "on") { $pageURL .= "s"; } $pageURL .= "://"; if ($_SERVER["SERVER_PORT"] != "80") { $pageURL .= $_SERVER["HTTP_HOST"] . ":" . $_SERVER["SERVER_PORT"] . $_SERVER["REQUEST_URI"]; } else { $pageURL .= $_SERVER["HTTP_HOST"] . $_SERVER["REQUEST_URI"]; } return $pageURL; }/** * 获取当前站点的访问路径根目录 * @return [type] [description] */function getSiteUrl() { $uri = $_SERVER['REQUEST_URI']?$_SERVER['REQUEST_URI']:($_SERVER['PHP_SELF']?$_SERVER['PHP_SELF']:$_SERVER['SCRIPT_NAME']); return 'http://'.$_SERVER['HTTP_HOST'].substr($uri, 0, strrpos($uri, '/')+1); }/** * 字符串截取,支持中文和其他编码 * @param [string] $str [字符串] * @param integer $start [起始位置] * @param integer $length [截取长度] * @param string $charset [字符串编码] * @param boolean $suffix [是否有省略号] * @return [type] [description] */function msubstr($str, $start=0, $length=15, $charset="utf-8", $suffix=true) { if(function_exists("mb_substr")) { return mb_substr($str, $start, $length, $charset); } elseif(function_exists('iconv_substr')) { return iconv_substr($str,$start,$length,$charset); } $re['utf-8'] = "/[\x01-\x7f]|[\xc2-\xdf][\x80-\xbf]|[\xe0-\xef][\x80-\xbf]{2}|[\xf0-\xff][\x80-\xbf]{3}/"; $re['gb2312'] = "/[\x01-\x7f]|[\xb0-\xf7][\xa0-\xfe]/"; $re['gbk'] = "/[\x01-\x7f]|[\x81-\xfe][\x40-\xfe]/"; $re['big5'] = "/[\x01-\x7f]|[\x81-\xfe]([\x40-\x7e]|\xa1-\xfe])/"; preg_match_all($re[$charset], $str, $match); $slice = join("",array_slice($match[0], $start, $length)); if($suffix) { return $slice."…"; } return $slice; }/** * php 实现js escape 函数 * @param [type] $string [description] * @param string $encoding [description] * @return [type] [description] */function escape($string, $encoding = 'UTF-8'){ $return = null; for ($x = 0; $x < mb_strlen($string, $encoding);$x ++) { $str = mb_substr($string, $x, 1, $encoding); if (strlen($str) > 1) { // 多字节字符 $return .= "%u" . strtoupper(bin2hex(mb_convert_encoding($str, 'UCS-2', $encoding))); } else { $return .= "%" . strtoupper(bin2hex($str)); } } return $return; }/** * php 实现 js unescape函数 * @param [type] $str [description] * @return [type] [description] */function unescape($str) { $str = rawurldecode($str); preg_match_all("/(?:%u.{4})|.{4};|&#\d+;|.+/U",$str,$r); $ar = $r[0]; foreach($ar as $k=>$v) { if(substr($v,0,2) == "%u"){ $ar[$k] = iconv("UCS-2","utf-8//IGNORE",pack("H4",substr($v,-4))); } elseif(substr($v,0,3) == "") { $ar[$k] = iconv("UCS-2","utf-8",pack("H4",substr($v,3,-1))); } elseif(substr($v,0,2) == "&#") { echo substr($v,2,-1).""; $ar[$k] = iconv("UCS-2","utf-8",pack("n",substr($v,2,-1))); } } return join("",$ar); }/** * 数字转人名币 * @param [type] $num [description] * @return [type] [description] */function num2rmb ($num) { $c1 = "零壹贰叁肆伍陆柒捌玖"; $c2 = "分角元拾佰仟万拾佰仟亿"; $num = round($num, 2); $num = $num * 100; if (strlen($num) > 10) { return "oh,sorry,the number is too long!"; } $i = 0; $c = ""; while (1) { if ($i == 0) { $n = substr($num, strlen($num)-1, 1); } else { $n = $num % 10; } $p1 = substr($c1, 3 * $n, 3); $p2 = substr($c2, 3 * $i, 3); if ($n != '0' || ($n == '0' && ($p2 == '亿' || $p2 == '万' || $p2 == '元'))) { $c = $p1 . $p2 . $c; } else { $c = $p1 . $c; } $i = $i + 1; $num = $num / 10; $num = (int)$num; if ($num == 0) { break; } } $j = 0; $slen = strlen($c); while ($j < $slen) { $m = substr($c, $j, 6); if ($m == '零元' || $m == '零万' || $m == '零亿' || $m == '零零') { $left = substr($c, 0, $j); $right = substr($c, $j + 3); $c = $left . $right; $j = $j-3; $slen = $slen-3; } $j = $j + 3; } if (substr($c, strlen($c)-3, 3) == '零') { $c = substr($c, 0, strlen($c)-3); } // if there is a '0' on the end , chop it out return $c . "整"; }/** * 特殊的字符 * @param [type] $str [description] * @return [type] [description] */function makeSemiangle($str) { $arr = array( '0' => '0', '1' => '1', '2' => '2', '3' => '3', '4' => '4', '5' => '5', '6' => '6', '7' => '7', '8' => '8', '9' => '9', 'A' => 'A', 'B' => 'B', 'C' => 'C', 'D' => 'D', 'E' => 'E', 'F' => 'F', 'G' => 'G', 'H' => 'H', 'I' => 'I', 'J' => 'J', 'K' => 'K', 'L' => 'L', 'M' => 'M', 'N' => 'N', 'O' => 'O', 'P' => 'P', 'Q' => 'Q', 'R' => 'R', 'S' => 'S', 'T' => 'T', 'U' => 'U', 'V' => 'V', 'W' => 'W', 'X' => 'X', 'Y' => 'Y', 'Z' => 'Z', 'a' => 'a', 'b' => 'b', 'c' => 'c', 'd' => 'd', 'e' => 'e', 'f' => 'f', 'g' => 'g', 'h' => 'h', 'i' => 'i', 'j' => 'j', 'k' => 'k', 'l' => 'l', 'm' => 'm', 'n' => 'n', 'o' => 'o', 'p' => 'p', 'q' => 'q', 'r' => 'r', 's' => 's', 't' => 't', 'u' => 'u', 'v' => 'v', 'w' => 'w', 'x' => 'x', 'y' => 'y', 'z' => 'z', '(' => '(', ')' => ')', '〔' => '[', '〕' => ']', '【' => '[', '】' => ']', '〖' => '[', '〗' => ']', '{' => '{', '}' => '}', '《' => '<', '》' => '>', '%' => '%', '+' => '+', '—' => '-', '-' => '-', '~' => '-', ':' => ':', '。' => '.', '、' => ',', ',' => '.', '、' => '.', ';' => ';', '?' => '?', '!' => '!', '…' => '-', '‖' => '|', '”' => '"', '“' => '"', ''' => '`', '‘' => '`', '|' => '|', '〃' => '"', ' ' => ' ','.' => '.'); return strtr($str, $arr); } /** * 下载 * @param [type] $filename [description] * @param string $dir [description] * @return [type] [description] */ function downloads($filename,$dir='./'){ $filepath = $dir.$filename; if (!file_exists($filepath)){ header("Content-type: text/html; charset=utf-8"); echo "File not found!"; exit; } else { $file = fopen($filepath,"r"); Header("Content-type: application/octet-stream"); Header("Accept-Ranges: bytes"); Header("Accept-Length: ".filesize($filepath)); Header("Content-Disposition: attachment; filename=".$filename); echo fread($file, filesize($filepath)); fclose($file); } } /** * 创建一个目录树 * @param [type] $dir [description] * @param integer $mode [description] * @return [type] [description] */ function mkdirs($dir, $mode = 0777) { if (!is_dir($dir)) { mkdirs(dirname($dir), $mode); return mkdir($dir, $mode); } return true; }
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php把负数转为正整数的方法:1、使用abs()函数将负数转为正数,使用intval()函数对正数取整,转为正整数,语法“intval(abs($number))”;2、利用“~”位运算符将负数取反加一,语法“~$number + 1”。

实现方法:1、使用“sleep(延迟秒数)”语句,可延迟执行函数若干秒;2、使用“time_nanosleep(延迟秒数,延迟纳秒数)”语句,可延迟执行函数若干秒和纳秒;3、使用“time_sleep_until(time()+7)”语句。

php除以100保留两位小数的方法:1、利用“/”运算符进行除法运算,语法“数值 / 100”;2、使用“number_format(除法结果, 2)”或“sprintf("%.2f",除法结果)”语句进行四舍五入的处理值,并保留两位小数。

判断方法:1、使用“strtotime("年-月-日")”语句将给定的年月日转换为时间戳格式;2、用“date("z",时间戳)+1”语句计算指定时间戳是一年的第几天。date()返回的天数是从0开始计算的,因此真实天数需要在此基础上加1。

php字符串有下标。在PHP中,下标不仅可以应用于数组和对象,还可应用于字符串,利用字符串的下标和中括号“[]”可以访问指定索引位置的字符,并对该字符进行读写,语法“字符串名[下标值]”;字符串的下标值(索引值)只能是整数类型,起始值为0。

方法:1、用“str_replace(" ","其他字符",$str)”语句,可将nbsp符替换为其他字符;2、用“preg_replace("/(\s|\ \;||\xc2\xa0)/","其他字符",$str)”语句。

在php中,可以使用substr()函数来读取字符串后几个字符,只需要将该函数的第二个参数设置为负值,第三个参数省略即可;语法为“substr(字符串,-n)”,表示读取从字符串结尾处向前数第n个字符开始,直到字符串结尾的全部字符。

php判断有没有小数点的方法:1、使用“strpos(数字字符串,'.')”语法,如果返回小数点在字符串中第一次出现的位置,则有小数点;2、使用“strrpos(数字字符串,'.')”语句,如果返回小数点在字符串中最后一次出现的位置,则有。


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SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.
