gistfile1.php

<?php
//Check if form was submitted
if (!isset($_GET['refund_addr'])) {
	//Protection from XSS attacks
	$url = htmlentities($_SERVER['PHP_SELF']);

	//Print out the form using heredoc syntax
    echo <<< EOT
    <form method="GET" action="$url">
    	Enter an address where we can send you refunds if necessary: 
    	<input type="text" name="refund_addr">
    	<br>
    	<input type="submit" value="Click to Pay">
    </form>
EOT;
return;
}

try {
  //Open the database - EDIT THIS TO CONNECT TO YOUR DB
	$db = new PDO('mysql:host=localhost;dbname=test', 'root', '');
} catch(Exception $e) {
	die($error);
}

//Create new invoice in table
$stmt = $db->prepare("INSERT INTO invoices VALUES(null, :refund_addr, 0)");
$stmt->execute(array(':refund_addr' => $_GET['refund_addr']));

//Get the ID of the invoice
$invoice_id = $db->lastInsertId();

$secret = 'ZzsMLGKe162CfA5EcG6j';
$my_address = '1Pqh1kXjMVa8KvSJFg9DoUoKz9G1kNiYvo';
$my_callback_url = 'https://mystore.com?invoice_id='.$invoice_id.'&secret='.$secret;
$root_url = 'http://blockchain.info/api/receive';
$parameters = 'method=create&address=' . $my_address .'&shared=false&callback='. urlencode($my_callback_url);
$response = file_get_contents($root_url . '?' . $parameters);
$object = json_decode($response);

echo "Your invoice ID is $invoice_id. Send payment to " . $object->input_address;