A simple and safe PHP authentication code class, PHP verification code _php Instance

One, sample verification code

Second, PHP Authentication code class, secoder.class.php

<?php/** * Security Verification Code to: Verify code text distort, rotate, use different fonts, add interference code * * @author Running water Mengchun <cmpan (at) qq.com> * @link http://l Abs.yulans.cn/yl_security_secoder * @link Http://wiki.yulans.cn/docs/yl/security/secoder * * Class Yl_security_ 
Secoder {/** * Verification Code of the session of the subscript * * @var string///public static $seKey = ' Sid.sek ey.ylans.cn '; 
public static $seKey = ' Sid '; public static $expire = 3000; Authenticode expiration (s)/** * code used in the character, 01IO easy to confuse, recommended not * * @var string/public static $codeSet = ' 346789ABCDEFGHJKLMNPQRTUVWX 
Y '; public static $fontSize = 25; Authenticode font size (px) public static $useCurve = true; Whether to draw a confusing curve public static $useNoise = true; Add pragma public static $imageH = 0; Verify code picture wide public static $imageL = 0; Verify code picture long public static $length = 4; Verify the number of code digits public static $BG = Array (243, 251, 254); Background protected static $_image = NULL; Verification code picture instance protected static $_color = NULL; Verify code Font Color/** * Output Verification code and save the value of the validation code in the session * Verify code saved to the session format: $_session[self:: $seKey] = array (' COde ' => ' Verification Code value ', ' time ' => ' verification Code created ');  */public static function entry () {//Picture width (px) Self:: $imageL | | self:: $imageL = self:: $length * Self:: $fontSize * 1.5 + 
Self:: $fontSize *1.5; Picture High (px) Self:: $imageH | | 
Self:: $imageH = self:: $fontSize * 2; 
Establish a self:: $imageL x Self:: $imageH image self::$_image = Imagecreate (self:: $imageL, Self:: $imageH); 
Set Background imagecolorallocate (Self::$_image, Self:: $BG [0], Self:: $BG [1], Self:: $BG [2]); 
CAPTCHA font random Color Self::$_color = imagecolorallocate (Self::$_image, Mt_rand (1,120), Mt_rand (1,120), Mt_rand (1,120)); The validation code uses a random font//$ttf = DirName (__file__). '/ttfs/'. Mt_rand (1, 20). '. TTF '; 4 $ttf = dirname (__file__). 
'/ttfs/4.ttf '; 
if (self:: $useNoise) {//Paint Miscellaneous point self::_writenoise (); 
} if (self:: $useCurve) {//Draw interference line self::_writecurve (); //Draw Verification Code $code = Array (); Verification code $codeNX = 0; 
The left margin for the nth character of the authentication code for ($i = 0; $i <self:: $length; $i + +) {$code [$i] = self:: $codeSet [Mt_rand (0, 27)]; $codeNX + + Mt_rand (self:: $fontSize *1.2, self::$fontsize*1.6); Write a captcha character imagettftext (Self::$_image, Self:: $fontSize, Mt_rand ( -40), $codeNX, self:: $fontSize *1.5, Self::$_color 
, $ttf, $code [$i]); }//Save Verification Code isset ($_session) | | 
Session_Start (); $_session[self:: $seKey] [' code '] = Join (", $code); Save the check code to session $_session[self:: $seKey [' time '] = time (); 
Verify Code creation Time Header (' Cache-control:private, max-age=0, No-store, No-cache, Must-revalidate '); 
Header (' cache-control:post-check=0, pre-check=0 ', false); 
Header (' Pragma:no-cache '); 
Header ("Content-type:image/png"); 
Output Image imagepng (self::$_image); 
Imagedestroy (Self::$_image); /** * Draw a random sine function curve that is composed of two lines (you can change to a more handsome curve function) * * The mathematical formula of the high school I forgot to go to Nirvana, write to * sine function analytic formula: Y=asin (ωx+φ) +b * The effect of each constant value on the function image: * A: Determine peak (i.e. multiple of longitudinal stretch compression) * B: Indicates the position of the waveform in the Y axis or the longitudinal distance (up and down) *φ: Determines the waveform and the position of the x axis or the transverse moving distance (left plus right minus) *ω: Determining the period (minimum positive period t=2π/∣ω∣) * * * * */protected S tatic function _writecurve () {$A = Mt_rand (1, Self:: $imageH/2);//Amplitude $b = Mt_rand (-self:: $imageH/4, Self:: $imageH/4); Y-axis Offset $f = Mt_rand (-self:: $imageH/4, Self:: $imageH/4); X axis Offset $T = Mt_rand (self:: $imageH *1.5, Self:: $imageL *2); 
Cycle $w = (2* m_pi)/$T; $px 1 = 0; The starting position of the curve axis $px 2 = Mt_rand (self:: $imageL/2, Self:: $imageL * 0.667); End position of curvilinear axis for ($px = $px 1; $px <= $px 2; $px = $px + 0.9) {if ($w!=0) {$py = $A * Sin ($w * $px + $f) + $b + self:: $imageH/ 2; 
y = Asin (ωx+φ) + b $i = (int) (self:: $fontSize-6)/4); while ($i > 0) {imagesetpixel (self::$_image, $px + $i, $py + $i, self::$_color);//Here The portrait is more than Imagettftext and imagestring performance. 
Much better $i--; }} $A = Mt_rand (1, Self:: $imageH/2); Amplitude $f = Mt_rand (-self:: $imageH/4, Self:: $imageH/4); X axis Offset $T = Mt_rand (self:: $imageH *1.5, Self:: $imageL *2); 
Cycle $w = (2* m_pi)/$T; 
$b = $py-$A * sin ($w * $px + $f)-Self:: $imageH/2; 
$PX 1 = $px 2; 
$px 2 = self:: $imageL; for ($px = $px 1; $px <= $px 2; $px = $px + 0.9) {if ($w!=0) {$py = $A * Sin ($w * $px + $f) + $b + self:: $imageH/2;//y = Asin 
(ωx+φ) + b $i = (int) (self:: $fontSize-8)/4); while ($i > 0) {imagesEtpixel (self::$_image, $px + $i, $py + $i, self::$_color); 
Here (while) the loop portrait element is much better than the Imagettftext and imagestring using the font size at once (without this while loop) $i--; 
/** * Draw Miscellaneous points * Write different color letters or numbers to the picture * * protected static function _writenoise () {for ($i = 0; $i < $i + +) { 
Miscellaneous point Color $noiseColor = Imagecolorallocate (Self::$_image, Mt_rand (150,225), Mt_rand (150,225), Mt_rand (150,225)); for ($j = 0; $j < 5; $j + +) {//Paint Miscellaneous point imagestring (Self::$_image, 5, Mt_rand ( -10, Self:: $imageL), Mt_rand ( -10, self: 
: $imageH), Self:: $codeSet [Mt_rand (0, 27)],//Miscellaneous point text is a random letter or number $noiseColor); /** * Verify that the verification code is correct * * @param string $code user authentication code * @param BOOL user authentication code is correct */public static function check ($code 
) {isset ($_session) | | | session_start (); Authenticode cannot be empty if (empty ($code) | | empty ($_session[self:: $seKey]) {//echo $_session[self:: $seKey [' Code ']. ' 
1 '; 
return false; 
//Session expiration if (time ()-$_session[self:: $seKey] [' time '] > Self:: $expire) {unset ($_session[self:: $seKey]); Echo $_seSsion[self:: $seKey] [' Code ']. ' 
2 '; 
return false; 
return 0; }//if ($code = = $_session[self:: $seKey [' Code ']) {if strtoupper ($code) = = $_session[self:: $seKey [' Code ']] {//case-insensitive More//echo $_session[self:: $seKey [' Code ']. ' 
3 '; 
return true; }//echo $_session[self:: $seKey [' Code ']. ' 
4 '; 
return false; }//useage/* Yl_security_secoder:: $useNoise = false; 
To be more secure, change to True yl_security_secoder:: $useCurve = true; 
Yl_security_secoder::entry (); */*//Verify code if (! 
Yl_security_secoder::check (@$_post[' Secode ')) {print ' Error secode '; } 
*/

Third, call the method

1, display the Authentication code page code.php

<?php 
session_start (); 
Require ' secoder.class.php '; First the class is included, the actual path is modified according to the actual situation. 
$vcode = new Yl_security_secoder ();//Instantiate an object 
$vcode->entry (); 
? >

2, check the verification code is correct

<?php 
session_start (); 
Require ' secoder.class.php '; First the class is included, the actual path is modified according to the actual situation. 
$vcode = new Yl_security_secoder ();//Instantiate an object 
//$vcode->entry (); 
$code = $_get[' code ']; 
echo $vcode->check ($code); 
$_session[' Code ' = $VC->getcode ()//Verify code is saved to session 
?>

3, Verification Code input Box call page

 click the picture to retrieve the verification code <br> 
<a href= "# ">

The above is a small set to introduce a simple and safe PHP code class, PHP verification code, I hope to help you, if you have any questions please give me a message, small series will promptly reply to everyone. Here also thank you very much for the cloud Habitat Community website support!