Thank you both for your replies.
Snookerman
What you mentioned makes since because most of the image CAPTCHA scripts that I looked at use some form of SESSION...so I started to look into things a little further since this seemed like it might be a little more in depth than I originally thought.
forum_amnesiac
Everything is contained in the same form and currently uses <?php echo $_SERVER['PHP_SELF']; ?> as the action. When I first started testing rand() was (0, 100). Interesting point about $sum = $num1.$num2; giving a larger value range.
I did some further research and found a script called Math Guard which uses a class file to create the question and check the answer. (once resolved I will post it all in the hopes that it will help someone else just wanting to add a simple check to their form.)
This seemed pretty easy to implement into my existing script, and it does the job to check for the correct answer (had to modify it to run in the same page as it was originally setup by the creator to post to another page). One issue with the math check condition though...
I added quite a few comments to explain what is going on
<?php
// start form processing which is located at the top of the page
if (isset($_POST['submit'])) {
$e = array(); // An empty array to hold possible error messages
// Everytime an error occurs, add an error message to the errors array.
if (!ereg("^[a-zA-Z]+$", $name) ) {
$e[] = 'Please enter name of person you\'re sending the message to<br>';
}
if ( $email=='' ) {
$e[] = 'Please enter the email address of the person you\'re sending the message to<br>';
}
if ( $mathguard_answer=='' ) {
$e[] = 'Please enter the answer to the math question<br>';
}
/* require the MathGuard class */
require ("ClassMathGuard.php");
if (MathGuard :: checkResult($_REQUEST['mathguard_answer'], $_REQUEST['mathguard_code'])) {
echo ("Correct answer!"); //insert your code that will be executed when user enters the correct answer
}
else {
$e[] = 'Bad answer, please try again!<br>';
}
if ( empty($e) ) { // If the errors array is empty, there were no errors and we can execute the rest of the script
//...all the code to mail the user or any other form processing needed
} // end empty($e) if
if ($e == NULL) {
$success = true; // proceed because everything is ok
}
}
?>
<html>
<head>
<title></title>
</head>
<body>
<?php
if ( isset($success) ) { // Form processing above has completed now the success result is being displayed to the user.
echo '<p>Thank you. Your message has been sent.</p>';
} else { // Form either hasn't been submitted or wasn't successful
if ( !empty($e) ) { // If errors array is not empty echo them
foreach ( $e as $msg ) {
echo $msg;
}
}
?>
<!--- HTML FORM HERE --->
<?php
} //close the final if statement
?>
The issue is with this portion from above...
if (MathGuard :: checkResult($_REQUEST['mathguard_answer'], $_REQUEST['mathguard_code'])) {
echo ("Correct answer!");
}
else {
$e[] = 'Bad answer, please try again!<br>';
}
I believe I need to change the if (MathGuard :: statement so it eliminates the correct answer message and only shows the error since all the other field checks are done like that, but I'm not sure how I can do this.
Right now when the math answer is correct it echos "Correct answer!" and the form is submitted without jumping down to if ( isset($success) ) {... like before implementing the Math Guard code.
This is the important part of the class file that checks the answer if it helps to change the MathGuard :: conditional statement (I'm not sure what the :: is doing above)
function checkResult($mathguard_answer, $mathguard_code, $prime = 37) {
$result_encoded = MathGuard::encode($mathguard_answer, $prime);
if ($result_encoded == $mathguard_code)
return true;
else
return false;
}
Again, I appreciate the help so far.