PHP - Authorize.net

I'm looking to build my own ecommerce site and i just looked at their sample code to test transactions. See below.

Code: [Select]
<?php
require_once 'anet_php_sdk/AuthorizeNet.php'; // Make sure this path is correct.
$transaction = new AuthorizeNetAIM('YOUR_API_LOGIN_ID', 'YOUR_TRANSACTION_KEY');
$transaction->amount = '9.99';
$transaction->card_num = '4007000000027';
$transaction->exp_date = '10/16';

$response = $transaction->authorizeAndCapture();

if ($response->approved) {
  echo "<h1>Success! The test credit card has been charged!</h1>";
  echo "Transaction ID: " . $response->transaction_id;
} else {
  echo $response->error_message;
}
?>
I was under the impression handling credit cards was MUCH harder to deal with. Couldn't you just store the $_POST['creditcardnumber'] in a database(not very secure AT ALL)? I would of thought they would have to make you mess with the form submission so their card number is encrpted through the $_POST and Authorize.net is the only one that has the decryption key. Also, doesn't like EVERY credit card processing form require the name on the card? Am i missing something??

I'm working with classes and don't know much about them. It's pulling data from authorize.net when a transaction is run. Maybe this is a general thing someone can help with? I include an AIM.class.php file in the page that process the transaction, 'registration4.php'. In the AIM.class.php I have this code that does print the transaction id to the page. The variable $pstr_trimmed looks like it gets used over and over for each 'case' :

Code: [Select]
case 7:
  echo "Transaction ID: ";
  echo $pstr_trimmed;
          /* thought I could just add $trans_id_variable = $pstr_trimmed; (didn't work */
  break;


But I don't know how to use that to type echo "$trans_id_variable" on register4.php or to insert it into my database?

Code: [Select]

<?php 
require("AIM2.class.php");

// here the data is set and the card processed, then...

if (!$approval = $aim->processCard("Workshops", $final_total)){
echo "<strong>Oops!</strong><br>Error proccessing credit card: " . print_r($aim->errorStack,1);
$appcodedesc = "Error processing credit card.";
$approval = 0;
}else{
// If we made it this far, the card was successfully charged
        // here the code echoes "Transaction ID: 1111111    Payment Approved"
echo "<strong><h3>Payment Approved</h3></strong><br>Successfully charged the credit card.  Add the attendee(s) name(s) below and submit. On the next page, you can print for your records. Please note that these are secure pages for payment processing, and pressing the back button in your browser, will bring up an expired page<br><br>"; // Approval code: " . $approval;
//echo $pstr_trimmed;
echo "and the new variable?";
       // but here's where I was hoping to take that transaction id and set it as a variable to put into the database.
echo $trans_id_test;
echo" should be before this";
$approval = 1;
$appcodedesc = "Payment Approved";