Response after invoice is created:

Array
(
    [InvoiceDate] => 2017-12-13 14:35:46
    [InvoiceNumber] => XK00023378
    [RandomNumber] => 2454
    [RtnCode] => 1
    [RtnMsg] => 開立發票成功
    [CheckMacValue] => DD4EE6FA77B7F833A6AB058311C310A6
)