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12,833 Points

Variable/Input Type issue

I'm not sure exactly what's going wrong here but trying to POST the question number isn't working. It seems like the values I'm getting when I try and post aren't integers, but I'm not sure why. Thanks in advance for any help!

<!DOCTYPE html>
<html lang="en">
    <meta charset="UTF-8">
    <title>Math Quiz: Addition</title>
    <link href='https://fonts.googleapis.com/css?family=Playfair+Display:400,400italic,700,700italic' rel='stylesheet' type='text/css'>
    <link rel="stylesheet" href="css/normalize.css">
    <link rel="stylesheet" href="css/styles.css">
    if (isset($_POST['page'])){
/// yes, I know I should sanitize the input, I was just trying different things to figure this out.
        $q_num = (int)$_POST['page'];
    } else {
    $q_num = 1;
$num_of_q = 10;

<?php var_dump($q_num);?>
    <div class="container">
        <div id="quiz-box">
            <p class="breadcrumbs">Question #<?= $q_num?> of <?= $num_of_q?></p>
            <p class="quiz">What is <?php 
            ?> </p>
            <form action="index.php" method="POST">
                <input type="hidden" name="page" value="<?php ($q_num+1);?>" />
                <input type="submit" class="btn" name="answer" value="135" />
                <input type="submit" class="btn" name="answer" value="125" />
                <input type="submit" class="btn" name="answer" value="115" />

1 Answer

9,458 Points

Based on the code provided, I would expect $q_num to be int(1) when the page is first loaded. After submitting the form, I would expect it to be int(0).

This is because nothing is being done with the result of ($q_num+1). If you want to use the result of this operation, then you'll need to echo it out. You can do this by changing the line with <?php ($q_num+1);?> to one of the following:

<input type="hidden" name="page" value="<?php echo ($q_num + 1); ?>" />
<input type="hidden" name="page" value="<?= ($q_num + 1) ?>" />