Skip to content

All topics  /  PHP

How To Generate Custom Captcha Code In PHP Example

PHP ·

Teams applying “How To Generate Custom Captcha Code In PHP Example” in a production project can use this reference page to record implementation, review and debugging time, then compare that effort with tests and shipped functionality instead of treating activity as performance by itself.

Before copying the example into a live application, confirm version-specific behaviour with the PHP project and test it against the project’s actual database and runtime.

How To Generate Custom Captcha Code In PHP Example

Hi guys,

Today i will explained How To create a custom captcha code generate in php. This example is so easy to use in php. This example to perform A generate form captcha code in manually.

This example to i am create a few files so follow my steps. I am create a asset/css/style.css file and script/captcha.php and script/contact_form.php directory folder inside.

So let's start to the example.

Index.php


<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>How To Generate Custom Captcha Code In PHP Example - Nicesnippets.com</title>
  <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.0/css/bootstrap.min.css">
  <link rel="stylesheet" href="assets/css/style.css">
</head>
<body>
  <div class="container mt-5">
    <?php include('scripts/contact_form.php'); ?>
    <?php if(!empty($captchaError)) {?>
      <div class="form-group col-12 text-center">
        <div class="alert text-center <?php echo $captchaError['status']; ?>">
          <?php echo $captchaError['message']; ?>
        </div>
      </div>
    <?php }?>
    <form action="" name="contactForm" method="post" enctype="multipart/form-data">
      <div class="form-group">
        <label>Name</label>
        <input type="text" class="form-control" name="name" id="name">
      </div>
      <div class="form-group">
        <label>Email</label>
        <input type="email" class="form-control" name="email" id="email">
      </div>
      <div class="row">
        <div class="form-group col-6">
          <label>Enter Captcha</label>
          <input type="text" class="form-control" name="captcha" id="captcha">
        </div>
        <div class="form-group col-6">
          <label>Captcha Code</label>
          <img src="scripts/captcha.php" alt="PHP Captcha">
        </div>
      </div>
      <input type="submit" name="send" value="Send" class="btn btn-dark btn-block">
    </form>
  </div>
</body>
</html>

assets/css/style.css 

.container {
  max-width: 500px;
  margin: 50px auto;
  text-align: left;
  font-family: sans-serif;
}
form {
  border: 1px solid #1A33FF;
  background: #ecf5fc;
  padding: 40px 50px 45px;
}
.form-control:focus {
  border-color: #000;
  box-shadow: none;
}
label {
  font-weight: 600;
}
.error {
  color: red;
  font-weight: 400;
  display: block;
  padding: 6px 0;
  font-size: 14px;
}
.form-control.error {
  border-color: red;
  padding: .375rem .75rem;
}

scripts/contact_form.php 

<?php
    session_start();

    
    if(!empty($_POST["send"])) {
      $name = $_POST["name"];
      $email = $_POST["email"];
      $captcha = $_POST["captcha"];
      $captchaUser = filter_var($_POST["captcha"], FILTER_SANITIZE_STRING);
      if(empty($captcha)) {
        $captchaError = array(
          "status" => "alert-danger",
          "message" => "Please enter the captcha."
        );
      }
      else if($_SESSION['CAPTCHA_CODE'] == $captchaUser){
        $captchaError = array(
          "status" => "alert-success",
          "message" => "Your form has been submitted successfuly."
        );
      } else {
        $captchaError = array(
          "status" => "alert-danger",
          "message" => "Captcha is invalid."
        );
      }
    }  
?>

scripts/captcha.php 

<?php
  session_start();
  // Generate captcha code
  $random_num    = md5(random_bytes(64));
  $captcha_code  = substr($random_num, 0, 6);
  // Assign captcha in session
  $_SESSION['CAPTCHA_CODE'] = $captcha_code;
  // Create captcha image
  $layer = imagecreatetruecolor(168, 37);
  $captcha_bg = imagecolorallocate($layer, 247, 174, 71);
  imagefill($layer, 0, 0, $captcha_bg);
  $captcha_text_color = imagecolorallocate($layer, 0, 0, 0);
  imagestring($layer, 5, 55, 10, $captcha_code, $captcha_text_color);
  header("Content-type: image/jpeg");
  imagejpeg($layer);
?>

Now you can check your own.

More on this topic