PHP variable depending on HTML input
I’m building a very simple calculator with PHP and HTML. Basically I want the user to put their state in and hit submit and when they do that, depending on the first letter I want it to generate what the total will be with the tax now added. What’s the best way to do this?
Here is what I have so far:
<?php $task = [ 'subtotal' => '$198.38', 'tax' => 'tbd', 'shipping' => '$5.00', 'grand_total' => false ]; require 'index.view.php';
<h1> Detailed Cost Breakdown</h1> <input name="state" placeholder="Enter Your State"> <button>Submit</button> <ul> <li> <strong>Subtotal: </strong> <?=$task['subtotal']; ?> </li> <li> <strong>Tax: </strong> <?=$task['tax']; ?> </li> <li> <strong>Shipping: </strong> <?=$task['shipping']; ?> </li> <li> <strong>Grand Total: </strong> </ul>