PHP Validating Randomly Generated Number

[wizzy886]

profit_calc.php

<?php
	
	$page_title = "Calculating Profit";
	include ('includes/header.php');

	$pnd = "&pound";

	$answer = $_POST['answer'];

	/*if (!defined($income && $costs)) {
		
	}*/
	if (!isset($_POST['answer'])) {
		$income= number_format(rand(50, 30000),1);
		$costs= number_format(rand(100, 20000),1);
	} else {
		$income_new = $income;
		$costs_new = $costs;
	}
?>

<div id="spacer"></div>
	<div id="title" class="text1"><h1><?php echo $page_title ?></h1></div>
<div id="spacer"></div>
	<div id="question" class="text2">

		<p>If a company makes a total turnover of <?php echo $pnd.$income; ?> and all the costs come to <?php echo $pnd.$costs; ?>.</p> 

			<p>What is the total profit made by this company?</P>

		<?php

				$profits= number_format($income_new-$costs_new, 1);

					if (!empty($_POST['answer'])) {
						number_format($answer, 1);
							if ($answer == $profits) {
								echo '<div class="correct"></div>';
							} else {
								echo '<div class="incorrect"></div>';
							}
					} else {
						$answer = NULL;
						echo "Enter in your answer below.";
					}

		?>

	</div>
<div id="spacer"></div>
	<div id="submit_box">
		<form action="profit_calc.php" method="POST" name="form">
			<input type="text" size="12" name="answer">
			<div id="input_submit"><input type="submit" name="submit" value="SUBMIT"></div>
		</form>
	</div>

<script type="text/javascript" language="JavaScript">
document.forms['form'].elements['answer'].focus();
</script>

<?php include ('includes/footer.php'); ?>

So basically I want this script to randomly generate two numbers that are then taken away from each other to give you another value. This value will then be validated and display whether you got it right or not. The bit I am struggling with is to get the randomly generated number to follow through to the validation of the actual answer itself. How would I go about doing this. Thank you in advance.

[requinix]

It looks like you're on the right track.

 

Put the generated numbers into the form as hidden inputs. Then in code get the value from the form (if it was submitted) or generate new ones (if not).

[wizzy886]

Now thats clever. I will have a shot at it. Thanks for quick reply. 

[wizzy886]

<?php
	
	$page_title = "Calculating Profit";
	include ('includes/header.php');

	$pnd = "&pound";

	$answer = $_POST['answer'];


	if (!defined($income && $costs)) {
		$income= number_format(rand(50, 30000),1);
		$costs= number_format(rand(100, 20000),1);	
	} else {
		if (empty($_POST['submitted_income' && 'submitted_costs'])) {
			$_POST['submitted_income'] = $income;
			$_POST['submitted_costs'] = $costs;
		}
	}
?>

<div id="spacer"></div>
	<div id="title" class="text1"><h1><?php echo $page_title ?></h1></div>
<div id="spacer"></div>
	<div id="question" class="text2">

		<p>If a company makes a total turnover of <?php echo $pnd.$income; ?> and all the costs come to <?php echo $pnd.$costs; ?>.</p> 

			<p>What is the total profit made by this company?</P>

		<?php

				$profits= number_format($_POST['submitted_income'] - $_POST['submitted_costs'], 1);

					if (!empty($_POST['answer'])) {
						number_format($answer, 1);
							if ($answer == $profits) {
								echo '<div class="correct"></div>';
							} else {
								echo '<div class="incorrect"></div>';
							}
					} else {
						$answer = NULL;
						echo "Enter in your answer below.";
					}

		?>

	</div>
<div id="spacer"></div>
	<div id="submit_box">
		<form action="profit_calc.php" method="POST" name="form">
			<input type="text" size="12" name="answer">
			<div id="input_submit"><input type="submit" name="submit" value="SUBMIT"></div>
			<input type="hidden" name="submitted_income" value="<?php echo $_POST['submitted_income']; ?>">
			<input type="hidden" name="submitted_costs" value="<?php echo $_POST['submitted_costs']; ?>">
		</form>
	</div>

<script type="text/javascript" language="JavaScript">
document.forms['form'].elements['answer'].focus();
</script>

<?php include ('includes/footer.php'); ?>

So I have written this and still no success. I am new to using this hidden form part, and wondered what I am doing and why it is wrong?

[Q695]

Hidden fields are for those just being used to hide data from a user, but keep it on the form.  try something else, like a text, instead of hidden.  the value will show up, and you can see it at the same time.