Question

My main page is index.php. I am using CAPTCHA in that, after submitting the form on that page it checks for CAPTCHA validation, if the value is correct then it goes to form.php. If the value is incorrect then it will stay on the same page.

My problem is if the CAPTCHA value is incorrect it comes to index.php and all values that I have entered in form are null. I want the values that I entered in the form, even if CAPTCHA is wrong and ask for new CAPTCHA text.

if(empty($_SESSION['6_letters_code'] ) || strcasecmp($_SESSION['6_letters_code'], $_POST['6_letters_code']) != 0)
{
    $errors .= "\n The above code does not match!";
}

if(empty($errors))
{
    header('Location:form.php');
}

function IsInjected($str)
{
    $injections = array('(\n+)',
        '(\r+)',
        '(\t+)',
        '(%0A+)',
        '(%0D+)',
        '(%08+)',
        '(%09+)'
    );

    $inject = join('|', $injections);
    $inject = "/$inject/i";
    if(preg_match($inject,$str))
    {
        return true;
    }
    else
    {
        return false;
    }
}

if(!empty($errors))
{
    header('Location:index.php');
    echo "The above code does not match!";  
}  

Answer 1

The simplest way is toy put your validation script on the same page of the form, and after validation if correct redirect user browser to another page, els let them be on the same form page…

Now put in your input fields like this presuming you are using POST method to send.

<input type="text" name="username" value="<?php echo isset($_POST['username'])? $_POST['username']:'';?>"

Same for remaining..

Or if you want to have your verification logic on some other page then use SESSION variables to transfer value between pages…
I hope I answered what what you are looking for..for anything else comment..:)