A simple and safe PHP Verification Code class with a call method, and a php verification code with a call

A simple and safe PHP Verification Code class with a call method, and a php verification code with a call

I. Verification code example

Ii. php Verification Code class, secoder. class. php

<? Php/*** security verification code **: The Verification Code text is distorted and rotated. Different fonts are used to add the interference code ** @ author streamline Meng Chun <cmpan () qq.com> * @ link http://labs.yulans.cn/YL_Security_Secoder * @ link http://wiki.yulans.cn/docs/yl/security/secoder */class YL_Security_Secoder {/*** subscripts of the Verification Code session ** @ var string * // public static $ seKey = 'sid. sek ey.ylans.cn '; public static $ seKey = 'sid'; public static $ expire = 3000; // characters used in the verification code expiration time (s)/***, 01 IO is easy to confuse. We recommend that you do not use ** @ var string */public static $ codeSet = 'your 89abcdefghjklmnpqrtuvwxy'; public static $ fontSize = 25; // The font size (px) of the verification code) public static $ useCurve = true; // whether to draw a confusion Curve public static $ useNoise = true; // whether to add a miscellaneous public static $ imageH = 0; // Verification Code Image Width public static $ imageL = 0; // Verification Code image length public static $ length = 4; // Verification Code digits public static $ bg = array (243,251,254 ); // background protected static $ _ image = Null; // The Verification Code image instance protected static $ _ color = null; // font color of the Verification Code/*** output the verification code and save * The verification code saved to the session in the format of $ _ session [self :: $ seKey] = array ('code' => 'verification code value', 'time' => 'verification code creation Time'); */public static function entry () {// image width (px) self ::$ imageL | self ::$ imageL = self ::$ length * self ::$ fontSize * 1.5 + self :: $ fontSize * 1.5; // Image Height (px) self: $ imageH | self ::$ imageH = self ::$ fontSize * 2; // create a picture Self ::$ imageL x self ::$ imageH's image self ::: _ image = imagecreate (self ::$ imageL, self ::$ imageH ); // set the background imagecolorallocate (self: $ _ image, self: $ bg [0], self: $ bg [1], self :: $ bg [2]); // random color of the Verification Code font self: $ _ color = imagecolorallocate (self: $ _ image, mt_rand (1,120), mt_rand (1,120 ), mt_rand (1,120); // The Verification Code uses a random font // $ ttf = dirname (_ FILE __). '/ttfs /'. mt_rand (1, 20 ). '. ttf'; 4 $ ttf = dirname (_ FILE __). '/ Ttfs/4. ttf'; if (self ::$ useNoise) {// plot the miscellaneous self ::_ writeNoise () ;}if (self ::$ useCurve) {// paint interference Line self: _ writeCurve () ;}// paint Verification code $ code = array (); // Verification code $ codeNX = 0; // The left margin of the N character of the verification 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 verification code character imagettftext (self ::$ _ image, self ::$ fontSize, mt_rand (-40, 70 ), $ CodeNX, self ::$ fontSize * 1.5, self ::$ _ color, $ ttf, $ code [$ I]);} // Save the verification code isset ($ _ SESSION) | session_start (); $ _ SESSION [self: $ seKey] ['code'] = join ('', $ code ); // Save the verification code to session $ _ SESSION [self: $ seKey] ['time'] = time (); // The verification 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 composed of two connected functions as an interference line (you can change it to a more handsome curve function) ** in high school, I forgot about the mathematical formula. I wrote the * sine function's analytical formula: y = Asin (ω x + PHI) + B *. The effects of various constant values on function images: * A: determines the peak value (that is, the multiple of the longitudinal tensile compression) * B: indicates the position of the waveform on the Y axis or the vertical moving distance (plus or minus) * Phi: determines the relationship between the waveform and the X-axis position or the horizontal moving distance (left plus right minus) * ω: determines the cycle (minimum positive cycle T = 2 π/∣ ω ∣) **/protected static function _ writeCurve () {$ A = mt_rand (1, self: $ imageH/2); // Zhen Frame $ B = mt_rand (-self ::$ imageH/4, self ::$ imageH/4); // offset of the Y axis direction $ f = mt_rand (-self :: $ imageH/4, self: $ imageH/4); // offset of the X axis direction $ T = mt_rand (self: $ imageH * 1.5, self :: $ imageL * 2); // period $ w = (2 * M_PI)/$ T; $ px1 = 0; // the starting position of the abscissa of the curve $ px2 = mt_rand (self :: $ imageL/2, self: $ imageL * 0.667); // curve X-axis end position for ($ px = $ px1; $ px <= $ px2; $ px = $ px + 0.9) {if ($ w! = 0) {$ py = $ A * sin ($ w * $ px + $ f) + $ B + self: $ imageH/2; // y = Asin (ω x + PHI) + B $ I = (int) (self: $ fontSize-6)/4); while ($ I> 0) {imagesetpixel (self ::$ _ image, $ px + $ I, $ py + $ I, self ::$ _ color ); // The image pixels here have much better performance than imagettftext and imagestring $ I -- ;}}$ A = mt_rand (1, self ::$ imageH/2 ); // amplitude $ f = mt_rand (-self: $ imageH/4, self: $ imageH/4); // offset of the X axis direction $ 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; $ px1 = $ px2; $ px2 = self: $ imageL; for ($ px = $ px1; $ px <= $ px2; $ px = $ px + 0.9) {if ($ w! = 0) {$ py = $ A * sin ($ w * $ px + $ f) + $ B + self: $ imageH/2; // y = Asin (ω x + PHI) + B $ I = (int) (self: $ fontSize-8)/4); while ($ I> 0) {imagesetpixel (self ::$ _ image, $ px + $ I, $ py + $ I, self ::$ _ color); // here (while) the performance of looping pixel points is much better than that of imagettftext and imagestring in the font size. $ I --;}}}} /*** draw a noise * write letters or numbers of different colors to the image */protected static function _ writeNoise () {for ($ I = 0; $ I <10; $ I ++) {// miscellaneous color $ noiseCol Or = imagecolorallocate (self: $ _ image, mt_rand (150,225), mt_rand (150,225), mt_rand (150,225); for ($ j = 0; $ j <5; $ j ++) {// draw a miscellaneous imagestring (self: $ _ image, 5, mt_rand (-10, self: $ imageL), mt_rand (-10, self:: $ imageH), self: $ codeSet [mt_rand (0, 27)], // The Miscellaneous text is a random letter or number $ noiseColor );}}} /*** verify that the verification code is correct ** @ param string $ code user verification code * @ param bool user verification code is correct */public static function check ($ code ){ Isset ($ _ SESSION) | session_start (); // The Verification code 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 (strto Upper ($ code) == _ SESSION [self: $ seKey] ['code']) {// case-insensitive comparison // echo $ _ SESSION [self :: $ seKey] ['code']. '3'; return true;} // echo $ _ SESSION [self: $ seKey] ['code']. '4'; return false ;}/// useage/* YL_Security_Secoder: $ useNoise = false; // change trueYL_Security_Secoder: $ useCurve = true to ensure higher security; YL_Security_Secoder :: entry (); * // verify the verification code if (! YL_Security_Secoder: check (@ $ _ POST ['secode']) {print 'error secret ';}*/

Iii. Call Methods

1. display the Verification code Page code. php

<? Php session_start (); require 'secoder. class. php'; // first include the class, and modify the actual path according to the actual situation. $ Vcode = new YL_Security_Secoder (); // instantiate an object $ vcode-> entry ();?>

2. Check whether the verification code is correct

<? Php session_start (); require 'secoder. class. php'; // first include the class, and modify the actual path 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 (); // The verification code is saved to the SESSION?>

3. Verification code input box call page

 click the image to obtain the verification code again <br> <a href = "#"> 

The above is all the content of this article. I hope it will be helpful for your learning and support for helping customers.