<?php # calculator.php
$page_title = 'Widget Cost Calculator';
include ('../includes/header.html');
// Check if the form has been submitted.
if (isset($_POST['submitted'])) {
// Minimal form validation.
if ( is_numeric($_POST['quantity']) && is_numeric($_POST['price'] && is_numeric($_POST['tax']) ) 

// Calculate the results.
$taxrate = $_POST['tax'] / 100; // Turn 5% into .05.
$total = ($_POST['quantity'] * $_POST['price']) * ($taxrate + 1);

// Print the results.
echo '<h1 id="mainhead"> Total Cost</h1>
<p> the total cost of purchasing ' . $_POST['quantity'] . ' widget(s) at $' . number_format ($_POST['price'], 2) . ' each, including a tax rate of ' . $_POST['tax'] . '%, is $' . number_format ($total, 2) . ' .</p><p><br /></p>';
} else { // Invalid submitted values.
echo '<h1 id="mainhead">Error!</h1>
<p class="error>Please enter a valid quantity, price and tax.</p><p><br /></p>';
}

} //End of main isset() IF.

// Leave the PHP section and create the HTML form.
?>
<h2>Widget Cost Calculator</h2>
< form action="calculator.php" method="post">
<p>Quantity: <input type="text" name="quantity" size="5" maxlength="10" /></p>
<p>Price: <input type="text" name="price" size="5" maxlength="10" /></p>
<p>Tax (%): <input type="text" name="tax" size="5" maxlength="10" /></p>
<p>input type= "submit" name="submit" value="Calculate!" /></p>

<input type= "hidden" name="submitted" value="TRUE" />

</form>

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

<?php # script 3.7 - dateform.php
$page_title = 'Calendar Form';
include ('../includes/header.html');

// This function makes three pull-down menus for the months, days, and years.

function make_calendar_pulldowns() {

// Make the months array.

$months = array (1 => 'January', 'Febuary', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December');

// Make the months pull down-menu.

echo '<select name="month">';
foreach ($months as $key => $value) {
echo "<option value=\"$key\">
$value</option>\n";

}

echo '</select>';

// Make the days pull-down menu.

echo '<select name="day">';
for ($day = 1; $day <=31; $day++) {
echo "<option value=\"$day\">$day</option>\n";

}

echo '</select>';

// Make the years pull-down menu.

echo '<select name="year">';
for ($year= 2007; $year <=2012; $year++) {
echo "<option value=\"$year\">$year</option>\n";

}

echo '</select>';

} //End of the function definition.

// Create the form tags.

echo '<h1 id="mainhead">Select a Date:</h1>
<p><br /></p><form action="dateform.php" 
method="post"';

// Call the function.

make_calendar_pulldowns();

echo '</form><p><br /></p>'; // End of form.

include ('../includes/footer.html');

?>