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//Add the using statements so you don’t have to
//type out the full namespace.
using Fortumo;
using FortumoWindows;
//Create the Fortumo object, use your Service ID and sercet.
//You can find your serviceID and secret from your Fortumo Dashboard - click the service and copy the lines Service ID and Secret here:
Payment p = new Payment("serviceID", "secret");
//Subscribe to the Completed event (see PaymentCompleted function below).
//Do this right after creating the Payment object to make sure that
//you don’t miss out on any “completed” notifications.
p.Completed += PaymentCompleted;
//Show the payment window. You should not call any UI specific code
//after this until the “Completed” event is triggered.
p.Show();