What are the best practices for implementing Captcha protection in PHP forms to prevent spam submissions?

To prevent spam submissions in PHP forms, implementing Captcha protection is a common practice. Captcha requires users to complete a challenge to prove they are not bots, thus reducing the number of automated spam submissions. 

// PHP code snippet for implementing Captcha protection in a form
session_start();

// Generate a random Captcha code
$captchaCode = rand(1000, 9999);
$_SESSION['captcha_code'] = $captchaCode;

// Display the Captcha image in the form
echo '<img src="captcha_image.php" alt="Captcha Image">';

// Validate the Captcha code entered by the user
if(isset($_POST['submit'])){
    $userCaptcha = $_POST['captcha'];
    if($userCaptcha == $_SESSION['captcha_code']){
        // Captcha code is correct, process the form submission
    } else {
        // Captcha code is incorrect, display an error message
        echo 'Invalid Captcha code. Please try again.';
    }
}

Keywords

Captcha PHP forms spam submissions implementation protection

Related Questions