<?php
 
    $params = array(
                'email'                     => $PAGSEGURO_EMAIL,  
                'token'                     => $PAGSEGURO_TOKEN,
                'creditCardToken'           => $creditCardToken,
                'senderHash'                => $senderHash,
                'receiverEmail'             => $PAGSEGURO_EMAIL,
                'paymentMode'               => 'default', 
                'paymentMethod'             => 'creditCard', 
                'currency'                  => 'BRL',
                'extraAmount'               => '1.00',
 
                'itemId1'                   => '0001',
                'itemDescription1'          => 'PHP Test',  
                'itemAmount1'               => $numero,  
                'itemQuantity1'             => 1,
 
                'itemId2'                   => '0002',
                'itemDescription2'          => 'PHP Test2',  
                'itemAmount2'               => $numero,  
                'itemQuantity2'             => 1
    );
 
    $filter = preg_grep('/^itemId([0-9]{1,})/', array_keys( $params ));
    $result = array();
    for($i = 0; $i < count($filter); $i++)
    {
 
        $result['itemId' . ($i + 1)] = $params['itemId' . ($i + 1)];
        $result['itemDescription' . ($i + 1)] = $params['itemDescription' . ($i + 1)];
        $result['itemAmount' . ($i + 1)] = $params['itemAmount' . ($i + 1)];
        $result['itemQuantity' . ($i + 1)] = $params['itemQuantity' . ($i + 1)];
 
    }
 
    var_dump($result);

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