Need Advice on PHP formail with captcha

Hi,

anyone have a recommendation on a php formmail with captcha

the captcha I am looking for is one with logic...such as:

1.) what's the sum of 23 and 40 ?
2.) or answering a simple question - the color of a banana , on sunny days, the sky is .? ( blue)

the image captchas with gif images seem to have problems with eye strain or simply unreadable text or numbers.

I need this for a hmtl application form & a contact form.

why..? b/c of those pesky spammers

last request - FREE is good or will pay small amount.

thanks

 

If you know PHP to an extent and know how to program your own form then adding this to your form will be easy. It's an PHP Captcha, however it does not have the logic questions you were seeking, sorry. (I can not post url's yet so replace the bold DOT with a period).

URL: www DOT white-hat-web-design.co.uk/articles/php-captcha.php

 

You can use this as a template:

<?php
session_start();
$scriptURL = "http://YOUR-DOMAIN/cap.php";
if(!empty($_POST['submit']) )
	{
	if(!empty( $_POST['comment'] )) { $theComment = $_POST['comment']; }
	if(!empty( $_POST['captcha'])) { $captcha = $_POST['captcha']; }

	if ($captcha != $_SESSION['captcha_code'])
		{
		$captchaERR = "Security code entry did not match. Please retry<br />";
		$formErrors = true;
		}
	if($formErrors) { ShowForm( $scriptURL, $captchaERR , $theComment); exit; }
	else { echo "Thank you for your comments"; exit; }
	
	}

else { ShowForm( $scriptURL ); }
exit;

################################################
# Build and show the form
function ShowForm( $scriptURL, $captchaERR = "", $theComment = "" )
{
$captcha = GetCaptcha();
echo '
<form action="' . $scriptURL . '" method="post">
<p>Feedback</p>
<textarea rows="4" name="comment" cols="40">'.$theComment.'</textarea>
<p>' . $captchaERR . $captcha . '<input type="text" name="captcha" value=""  size="50" /></p>
<p align="center"><input type="submit" value="Send Feedback" name="submit" /></p>
</form>';

}

function GetCaptcha()
{
$numA = rand(10, 50);
$numB = rand(10, 50);
$sum = $numA + $numB;
$_SESSION['captcha_code'] = $numA + $numB;
$question = "What is the sum of $numA and $numB?";
return $question;
}

?>

PHP:

 

IMO a simple text CAPTCHA like adding numbers isn't really going to stop bots.

 

Why do you say that? Bots can not read images?

 

$_SERVER['HTTP_REFERER'] == 'your form'
accept
ELSE
deny

---- and -----

Real IP Adress
http://www.soyturk.com/code/real_ip_adress.phps

---- and -----

he login to form page time
md5(time());

---- and ------

1. referer
2. ip
3. time

writing to sql or txt or .....
txt name is xxxxadasda (time, ip vs. vs. vs. )

session txt name;

after posted

control
txt is exists
open txt
referer = referer
ip = ip
time = time

Accepted

Else

Deny

 

For me it stops %99.99 of them.

Use this script:

http://www.free-php-scripts.net/P/Contact_Form

or implement it yourself:

http://www.phptricks.com/lesson.php?id=32

Peace,

 

I was replying to the post above mine that gave a text captcha (not image.)

 

Actually, they can. Most captcha images can be bypassed by good bots. But as azizny said, it stops most of them.

 

Thank u so much. gr8 script. like it.