<?php

include 'vendor/autoload.php';
$pagseguro = new WebDevBr\PagSeguro\PagSeguro();
$body = $pagseguro->payment(['email' => '*****@*****.**', 'token' => '95112EE828D94278BD394E91C', 'currency' => 'BRL', 'itemId1' => '0001', 'itemDescription1' => 'Notebook Prata', 'itemAmount1' => '24300.00', 'itemQuantity1' => '1', 'itemWeight1' => '1000', 'itemId2' => '0002', 'itemDescription2' => 'Notebook Rosa', 'itemAmount2' => '25600.00', 'itemQuantity2' => '2', 'itemWeight2' => '750', 'reference' => 'REF1234', 'senderName' => 'Jose Comprador', 'senderAreaCode' => '11', 'senderPhone' => '56273440', 'senderEmail' => '*****@*****.**', 'shippingType' => '1', 'shippingAddressStreet' => 'Av. Brig. Faria Lima', 'shippingAddressNumber' => '1384', 'shippingAddressComplement' => '5o andar', 'shippingAddressDistrict' => 'Jardim Paulistano', 'shippingAddressPostalCode' => '01452002', 'shippingAddressCity' => 'Sao Paulo', 'shippingAddressState' => 'SP', 'shippingAddressCountry' => 'BRA']);
var_dump($body);
<?php

include 'vendor/autoload.php';
$pagseguro = new WebDevBr\PagSeguro\PagSeguro();
$body = $pagseguro->notifications(['notificationCode' => '49E41C-8A1B1E1B1E01-0994CF1FBC5D-CD5BC9', 'email' => '*****@*****.**', 'token' => '95112EE828D94278BD394E91C4388F20']);
var_dump($body);
//Gambiarra para passar para array, não vejo motivo pra isso, porém... vai saber
var_dump(json_decode(json_encode($body), true));