PHP:
<html>
<body>
<form action="" method="post">
<?php
require_once('recaptchalib.php');
// Get a key from https://www.google.com/recaptcha/admin/create
$publickey = "geheim!";
$privatekey = "geheim!";
# the response from reCAPTCHA
$resp = null;
# the error code from reCAPTCHA, if any
$error = null;
# was there a reCAPTCHA response?
if ($_POST["recaptcha_response_field"]) {
$resp = recaptcha_check_answer ($privatekey,
$_SERVER["REMOTE_ADDR"],
$_POST["recaptcha_challenge_field"],
$_POST["recaptcha_response_field"]);
if ($resp->is_valid) {
echo "You got it!";
} else {
# set the error code so that we can display it
$error = $resp->error;
}
}
echo recaptcha_get_html($publickey, $error);
?>
<br/>
<input type="submit" value="submit" />
</form>
</body>
</html>
