php captcha Archives

CAPTCHA stands for "Completely Automated Public Turing test to tell Computers and Humans Apart", it’s a very common functionality to use at the time of submit data to prevent machines' access of your website. In this post, we will develop CAPTCHA script using PHP with help of easy three steps. This is a very basic captcha that is generated by PHP. The following files will use in this Captcha Example catpcha.jpg - A Image for the captchacaptcha.php - This file is used to generate a captcha with PHP using PHP session.index.php - This file is used to show the captcha image to the end user. Demo Sample Implement CAPTCHA Using PHP Step 1-We will put the capcha image in the project folder. This image will be used to generate a captcha image using the PHP GD library. This is a only dependency(GD library) with this example. Download Image You can use save as image option as well using right click. Step 2- We need to create a new file captcha.php file in project and put the blow PHP code into this file. <?php session_start(); header("Expires: Mon, 26 Jul 1997 05:00:00 GMT"); header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT"); header("Cache-Control: no-store, no-cache, must-revalidate"); header("Cache-Control: post-check0, pre-check0", false); header("Pragma: no-cache"); function _generateRandom($length6) { $_rand_src array( array(48,57) //digits , array(97,122) //lowercase chars // , array(65,90) //uppercase chars ); srand ((double) microtime() * 1000000); $random_string ""; for($i0;$i<$length;$i++){ $i1rand(0,sizeof($_rand_src)-1); $random_string . chr(rand($_rand_src,$_rand_src)); } return $random_string; } $im @imagecreatefromjpeg("captcha.jpg"); $rand _generateRandom(3); $_SESSION $rand; ImageString($im, 5, 2, 2, $rand." ".$rand." ".$rand." ", ImageColorAllocate ($im, 0, 0, 0)); $rand _generateRandom(3); ImageString($im, 5, 2, 2, " ".$rand." ".$rand." ".$rand, ImageColorAllocate ($im, 255, 0, 0)); Header ('Content-type: image/jpeg'); imagejpeg($im,NULL,100); ImageDestroy($im); ?> This file is used to generate a CAPTCHA image using the GD library and rendered to the view page of the project where it will call. Step 3-We will create a template file index.php in the project folder and put the below PHP code into this file. A Simple Example Of PHP CAPTCHA Script CAPTHCA is valid; proceed the message '; } else { echo ' CAPTHCA is not valid; ignore submission '; } ?> Email address: Password: Anti Spam code, Please Enter 3 Black Symbols Submit In the above code, I am creating an HTML form to show a captcha image and display captcha validation messages to the user. Demo & Download Code Of CAPTCHA Script with PHP Download Source Code Live Demo Please feel free to send queries to me using below comment section.

php captcha

A Simple CAPTCHA Script Using PHP

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php captcha

A Simple CAPTCHA Script Using PHP

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