calculator

Posted on 16th Feb 2014 07:03 pm by admin

I can't figure out why this code doesn't work. No error messages. Page loads.

Code: <?php # Script 3.9 - calculator.php
$page_title = 'Widget Cost Calculator';
include ('./header.html');



function calculate_total ($tax= 5) {
global $total;
$taxrate = $tax / 100;
$total = ($_POST['quantity'] * $_POST['price']) * ($taxrate + 1);
$total = number_format ($total, 2);
}


if (isset($_POST['submitted'])) {

if (is_numeric($_POST['quantity']) && is_numeric($_POST['price'])) {


echo '<h1 id="mainhead">Total Cost</h1>';

$total = NULL;

if (is_numeric($_POST['tax'])) {
calculate_total ($_POST['tax']);
} else {
calculate_total ();
}

echo '<p>The total cost of purchasing '. $_POST['quantity'] .' widget(s) at $'.
number_format ($_POST['price'], 2). ' each is $'. $total .'.</p>';

echo '<p><br/></p>';

} else {

echo '<h1 id="mainhead">Error!</h1>
<p class="error">Please enter a valid quantity and price.</p><p><br/></p>';
}

}

?>
<h2>Widget Cost Calculator</h2>
<form action="calculator.php" method="post">
<p>Quantity: <input type="text" name="quantity" size="5" maxlength="10" value="<?php if (isset($_POST['quantity'])) echo $_POST['quantity'];?>"/></p>
<p>Price: <input type="text" name="price" size="5" maxlength="10" value="<?php if (isset($_POST['price'])) echo $_POST['price'];?>"/></p>
<p>Tax (%): <input type="text" name="tax" size="5" maxlength="10" value="<?php if (isset($_POST['tax'])) echo $_POST['tax'];?>"/>(optional)</p>
<p><input type="submit" name"submit" value="Calculate!"/></p>
<input type="hidden" name"submitted" value="TRUE"/>
</form>


<?php
include ('./footer.html');
?>The calculator does not work and won't display anything. I've checked the code three times in the text book and I believe their is no typo's. What am I doing wrong?

Your Answer:

Login to answer

Other forums

HTML Viewer HIDE scrollbar
How can I disable scrollbars in a HTML Viewer control? I can't hide them. Even i have enough space b

Multi language - seo links
Im trying to figure out the best method to have a multi language website that will function with seo

Do While statement
hi guys,

This may sound trivial but im new to php and as part of an assignmenti have to const

First root of a number
Hi,

I can't find any function in php to give me the first root of a number.
Is there any

Show specific day of the week
I have been racking my brain trying to get this function to work properly and it is doing so for eve

I face problems to extract data from one table and insert it in another one
Hi,

For modifications, I have to extract data from one table and insert it in another one

Automatic Webpage ??
I have a page www.mysite.com/test.php with a
<form>
<textarea name=&q

Undefined Variable: PHP_SELF, pls help
Hi,

Im a newbie on PHP / MySQL programming and Im running a script to search one field on my

array & querys help/advice.
Ok so here goes , I have a mysql database and basically here's what I need to do.

// foreach

Checking if field is empty AND using !is_numeric
Hi lads,

Need to be able to display an error message (using isset?) that says "Cant lea