Captcha image verification

Hello Awais here.
i used this code in my login page but the doesn't appear on the login page.what should i do now?
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Veselin: most probably you did not put the code on the right place

Manor posted on November 14, 2008, 8:52 pm

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /home/man0r/domains/israel-fm.co.il/public_html/tests/mailto.php:2)
Any ideas on how to fix it?
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Veselin: please make sure you put session_start() at the very top of your file

vaibhav posted on November 13, 2008, 8:53 am

This is one of the best code u have write for the captcha image validation..
Thank fot that
do u have code for captcha image with numbers and alphabates.
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Veselin: you should replace
$text = rand(10000,99999);
with
$text = strtoupper(substr(str_shuffle('0123456789abcdefghjkmnpqrstuvwxyz'), 0, 4));

Gabe posted on September 13, 2008, 6:36 am

I can't get this code to bounce an invalid number. It will tell me that the number is wrong, but the form will still submit.
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Veselin: the code that processes the form data should be within the IF statement where echo 'Incorrect verification code. '; is.

Rich posted on August 22, 2008, 8:07 pm

All is well but the actual form submission. Here is what I have for submit.php. I suspect it is wrong. What to do?

<?
session_start();
if ($_POST["vercode"] != $_SESSION["vercode"] OR $_SESSION["vercode"]=='') {
echo 'Incorrect verification code. ';
} else {
// add form data processing code here
'<form ACTION="http://www.my_domain_name.com/cgi-bin/formmail.pl" METHOD="POST">'
;
};
?>
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Veselin: you need to put PHP code which takes the form data and process it (save it to file or database, email, etc..)

Ghapios posted on August 21, 2008, 5:23 pm

Good script, I integrated this into my site in an contact form, but it doesn't block who insert the wrong image code!
I'm wondering if this string should have more code:

if ($_POST["vercode"] != $_SESSION["vercode"] OR $_SESSION["vercode"]=='') {
echo 'Incorrect verification code. 

This also say that the image code is wrong but don't block the post.
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Veselin: try to print these two variables _POST["vercode"] and $_SESSION["vercode"] and see what values they have when you submit the form.

Akshath posted on July 25, 2008, 6:26 am

Works perfect !! Thank you very much.

pong posted on July 14, 2008, 6:57 pm

Hiya, I'm also getting weird text each time I load the captcha script (the php file) by itself. I'm also wondering if the integer type $text is typecasted into a string when it is used as a parameter in imagestring();.

Daniel Bithell posted on July 10, 2008, 9:22 pm

Fatal error: Call to undefined function imagecreate() in /home/******/public_html/captcha.php on line 9

Any ideas on how to fix?
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Veselin: this means that PHP version on your server does not support the image functions used to create the image


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Verification