Look at the renderings first
The paths of fonts and font files need to be set in $FontFilePath and $FontFileName in the class. For example:
private static $FontFilePath = "static/font/"; //relatively The location of this code file
private static $FontFileName = array("3.ttf");// array("1.ttf", "2.ttf", "3.ttf", "4.ttf", "5.ttf", "6.ttf", "7.ttf", "8.ttf"); //
The complete code is as follows:
/**
说明: 验证码生成类,支持生成Gif图片验证码(带噪点,干扰线,网格,随机色背景,随机自定义字体,倾斜,Gif动画)
服务端:
$mod = strtolower(isset($_REQUEST["mod"]) ? $_REQUEST["mod"] : "");
if($mod == "code"){
echo SecurityCode::Draw(4, 1, 120, 30, 5, 10, 100, "secode");
die();
}
调用:
验证:
$reqCode = strtolower(isset($_REQUEST["secode"]) ? $_REQUEST["secode"] : ""); //请求的验证码
$sessionCode = strtolower(isset($_SESSION["secode"]) ? $_SESSION["secode"] : ""); //会话生成的验证码
if($reqCode != $sessionCode){
echo "安全验证码错误!";
die();
}
*/
$mod = strtolower(isset($_REQUEST["mod"]) ? $_REQUEST["mod"] : "");
if ($mod == "code") {
echo SecurityCode::Draw(4, 15, 100, 27, 10, 2, 100, "secode");
die();
}
//安全验证码类
class SecurityCode {
private static $Debug = 0;
private static $Code = '';
private static $Chars = 'bcdefhkmnrstuvwxyABCDEFGHKMNPRSTUVWXY34568';
//private static $Chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890';
private static $TextGap = 20;
private static $TextMargin = 5;
private static $FontFilePath = "static/font/"; //相对地本代码文件的位置
private static $FontFileName =array("3.ttf");// array("1.ttf", "2.ttf", "3.ttf", "4.ttf", "5.ttf", "6.ttf", "7.ttf", "8.ttf"); //
private static $Img = 'GIF89a'; //GIF header 6 bytes
private static $BUF = Array();
private static $LOP = 0;
private static $DIS = 2;
private static $COL = -1;
private static $IMG = -1;
/**
生成GIF图片验证
@param int $L 验证码长度
@param int $F 生成Gif图的帧数
@param int $W 宽度
@param int $H 高度
@param int $MixCnt 干扰线数
@param int $lineGap 网格线间隔
@param int $noisyCnt 澡点数
@param int $sessionName 验证码Session名称
*/
public static function Draw($L = 4, $F = 1, $W = 150, $H = 30, $MixCnt = 2, $lineGap = 0, $noisyCnt = 10, $sessionName = "Code") {
ob_start();
ob_clean();
for ($i = 0; $i self::$Code .= SubStr(self::$Chars, mt_rand(0, strlen(self::$Chars) - 1), 1);
}
if (!isset($_SESSION))
session_start();
$_SESSION[$sessionName] = strtolower(self::$Code);
$bgRGB = array(rand(0, 255), rand(0, 255), rand(0, 255));
//生成一个多帧的GIF动画
for ($i = 0; $i $img = ImageCreate($W, $H);
//背景色
$bgColor = imagecolorallocate($img, $bgRGB[0], $bgRGB[1], $bgRGB[2]);
ImageColorTransparent($img, $bgColor);
unset($bgColor);
//添加噪点
$maxNoisy = rand(0, $noisyCnt);
$noisyColor = imagecolorallocate($img, rand(0, 255), rand(0, 255), rand(0, 255));
for ($k = 0; $k imagesetpixel($img, rand(0, $W), rand(0, $H), $noisyColor);
}
//添加网格
if ($lineGap > 0) {
for ($m = 0; $m imageline($img, $m * $lineGap, 0, $m * $lineGap, $H, $noisyColor);
}
for ($n = 0; $n imageline($img, 0, $n * $lineGap, $W, $n * $lineGap, $noisyColor);
}
}
unset($noisyColor);
// 添加干扰线
for ($k = 0; $k $wr = mt_rand(0, $W);
$hr = mt_rand(0, $W);
$lineColor = imagecolorallocate($img, rand(0, 255), rand(0, 255), rand(0, 255));
imagearc($img, $W - floor($wr / 2), floor($hr / 2), $wr, $hr, rand(90, 180), rand(180, 270), $lineColor);
unset($lineColor);
unset($wr, $hr);
}
//第一帧忽略文字
if ($i != 0 || $F //文字
$foreColor = imagecolorallocate($img, rand(0, 255), rand(0, 255), rand(0, 255));
for ($j = 0; $j $fontFile = self::$FontFilePath . self::$FontFileName[rand(0, count(self::$FontFileName) - 1)];
if (!file_exists($fontFile))
imagestring($img, 4, self::$TextMargin + $j * self::$TextGap, ($H - rand($H / 2, $H)), self::$Code[$j], $foreColor);
else
imageTTFtext($img, rand(15, 18), rand(-15, 15), self::$TextMargin + $j * self::$TextGap, ($H - rand(7, 10)), $foreColor, $fontFile, self::$Code[$j]);
}
unset($foreColor);
}
ImageGif($img);
Imagedestroy($img);
$Imdata[] = ob_get_contents();
OB_clean();
}
unset($W, $H, $B);
if (self::$Debug) {
echo $_SESSION['code'];
echo '
', Var_Dump($Imdata), '';
die();
}
header('Content-type:image/gif');
return self::CreateGif($Imdata, 20);
unset($Imdata);
}
private static function CreateGif($GIF_src, $GIF_dly = 10, $GIF_lop = 0, $GIF_dis = 0, $GIF_red = 0, $GIF_grn = 0, $GIF_blu = 0, $GIF_mod = 'bin') {
if (!is_array($GIF_src) && !is_array($GIF_tim)) {
throw New Exception('Error:' . __LINE__ . ',Does not supported function for only one image!!');
die();
}
self::$LOP = ($GIF_lop > -1) ? $GIF_lop : 0;
self::$DIS = ($GIF_dis > -1) ? (($GIF_dis self::$COL = ($GIF_red > -1 && $GIF_grn > -1 && $GIF_blu > -1) ? ($GIF_red | ($GIF_grn for ($i = 0, $src_count = count($GIF_src); $i if (strToLower($GIF_mod) == 'url') {
self::$BUF[] = fread(fopen($GIF_src[$i], 'rb'), filesize($GIF_src[$i]));
} elseif (strToLower($GIF_mod) == 'bin') {
self::$BUF[] = $GIF_src[$i];
} else {
throw New Exception('Error:' . __LINE__ . ',Unintelligible flag (' . $GIF_mod . ')!');
die();
}
if (!(Substr(self::$BUF[$i], 0, 6) == 'GIF87a' Or Substr(self::$BUF[$i], 0, 6) == 'GIF89a')) {
throw New Exception('Error:' . __LINE__ . ',Source ' . $i . ' is not a GIF image!');
die();
}
for ($j = (13 + 3 * (2 switch (self::$BUF[$i]{$j}) {
case '!':
if ((substr(self::$BUF[$i], ($j + 3), 8)) == 'NETSCAPE') {
throw New Exception('Error:' . __LINE__ . ',Could not make animation from animated GIF source (' . ($i + 1) . ')!');
die();
}
break;
case ';':
$k = FALSE;
break;
}
}
}
self::AddHeader();
for ($i = 0, $count_buf = count(self::$BUF); $i self::AddFrames($i, $GIF_dly);
}
self::$Img .= ';';
return (self::$Img);
}
private static function AddHeader() {
$i = 0;
if (ord(self::$BUF[0]{10}) & 0x80) {
$i = 3 * (2 self::$Img .= substr(self::$BUF[0], 6, 7);
self::$Img .= substr(self::$BUF[0], 13, $i);
self::$Img .= "!\377\13NETSCAPE2.0\3\1" . chr(self::$LOP & 0xFF) . chr((self::$LOP >> 8) & 0xFF) . "\0";
}
unset($i);
}
private static function AddFrames($i, $d) {
$L_str = 13 + 3 * (2 $L_end = strlen(self::$BUF[$i]) - $L_str - 1;
$L_tmp = substr(self::$BUF[$i], $L_str, $L_end);
$G_len = 2 $L_len = 2 $G_rgb = substr(self::$BUF[0], 13, 3 * (2 $L_rgb = substr(self::$BUF[$i], 13, 3 * (2 $L_ext = "!xF9x04" . chr((self::$DIS > 0) & 0xFF) . chr(($d >> 8) & 0xFF) . "x0x0";
if (self::$COL > -1 && ord(self::$BUF[$i]{10}) & 0x80) {
for ($j = 0; $j if (ord($L_rgb{3 * $j + 0}) == (self::$COL >> 0) & 0xFF && ord($L_rgb{3 * $j + 1}) == (self::$COL >> 8) & 0xFF && ord($L_rgb{3 * $j + 2}) == (self::$COL >> 16) & 0xFF) {
$L_ext = "!xF9x04" . chr((self::$DIS > 0) & 0xFF) . chr(($d >> 8) & 0xFF) . chr($j) . "x0";
break;
}
}
}
switch ($L_tmp{0}) {
case '!':
$L_img = substr($L_tmp, 8, 10);
$L_tmp = substr($L_tmp, 18, strlen($L_tmp) - 18);
break;
case ',':
$L_img = substr($L_tmp, 0, 10);
$L_tmp = substr($L_tmp, 10, strlen($L_tmp) - 10);
break;
}
if (ord(self::$BUF[$i]{10}) & 0x80 && self::$IMG > -1) {
if ($G_len == $L_len) {
if (self::Compare($G_rgb, $L_rgb, $G_len)) {
self::$Img .= ($L_ext . $L_img . $L_tmp);
} else {
$byte = ord($L_img{9});
$byte |= 0x80;
$byte &= 0xF8;
$byte |= (ord(self::$BUF[0]{10}) & 0x07);
$L_img{9} = chr($byte);
self::$Img .= ($L_ext . $L_img . $L_rgb . $L_tmp);
}
}else {
$byte = ord($L_img{9});
$byte |= 0x80;
$byte &= 0xF8;
$byte |= (ord(self::$BUF[$i]{10}) & 0x07);
$L_img{9} = chr($byte);
self::$Img .= ($L_ext . $L_img . $L_rgb . $L_tmp);
}
} else {
self::$Img .= ($L_ext . $L_img . $L_tmp);
}
self::$IMG = 1;
}
private static function Compare($G_Block, $L_Block, $Len) {
for ($i = 0; $i if ($G_Block{3 * $i + 0} != $L_Block{3 * $i + 0} || $G_Block{3 * $i + 1} != $L_Block{3 * $i + 1} || $G_Block{3 * $i + 2} != $L_Block{3 * $i + 2}) {
return (0);
}
}
return (1);
}
}
用法在类开头的注释里。

Thedifferencebetweenunset()andsession_destroy()isthatunset()clearsspecificsessionvariableswhilekeepingthesessionactive,whereassession_destroy()terminatestheentiresession.1)Useunset()toremovespecificsessionvariableswithoutaffectingthesession'soveralls

Stickysessionsensureuserrequestsareroutedtothesameserverforsessiondataconsistency.1)SessionIdentificationassignsuserstoserversusingcookiesorURLmodifications.2)ConsistentRoutingdirectssubsequentrequeststothesameserver.3)LoadBalancingdistributesnewuser

PHPoffersvarioussessionsavehandlers:1)Files:Default,simplebutmaybottleneckonhigh-trafficsites.2)Memcached:High-performance,idealforspeed-criticalapplications.3)Redis:SimilartoMemcached,withaddedpersistence.4)Databases:Offerscontrol,usefulforintegrati

Session in PHP is a mechanism for saving user data on the server side to maintain state between multiple requests. Specifically, 1) the session is started by the session_start() function, and data is stored and read through the $_SESSION super global array; 2) the session data is stored in the server's temporary files by default, but can be optimized through database or memory storage; 3) the session can be used to realize user login status tracking and shopping cart management functions; 4) Pay attention to the secure transmission and performance optimization of the session to ensure the security and efficiency of the application.

PHPsessionsstartwithsession_start(),whichgeneratesauniqueIDandcreatesaserverfile;theypersistacrossrequestsandcanbemanuallyendedwithsession_destroy().1)Sessionsbeginwhensession_start()iscalled,creatingauniqueIDandserverfile.2)Theycontinueasdataisloade

Absolute session timeout starts at the time of session creation, while an idle session timeout starts at the time of user's no operation. Absolute session timeout is suitable for scenarios where strict control of the session life cycle is required, such as financial applications; idle session timeout is suitable for applications that want users to keep their session active for a long time, such as social media.

The server session failure can be solved through the following steps: 1. Check the server configuration to ensure that the session is set correctly. 2. Verify client cookies, confirm that the browser supports it and send it correctly. 3. Check session storage services, such as Redis, to ensure that they are running normally. 4. Review the application code to ensure the correct session logic. Through these steps, conversation problems can be effectively diagnosed and repaired and user experience can be improved.

session_start()iscrucialinPHPformanagingusersessions.1)Itinitiatesanewsessionifnoneexists,2)resumesanexistingsession,and3)setsasessioncookieforcontinuityacrossrequests,enablingapplicationslikeuserauthenticationandpersonalizedcontent.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

Dreamweaver Mac version
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

SublimeText3 Chinese version
Chinese version, very easy to use

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool
