Cancelling Documents using DI API

Good day,

I am developing a code where I have to cancel a documents using DI API SDK.

I see some documents using the method Cancel and ther others using the method

CreateCancellationDocument.

For Example:

The Sales Orders use the Method: ObjectOrder.Cancel()

The Invoices use the method: ObjectTarget = ObjectInvoice.CreateCancellationDocument()

The Question is, How do i know which documents use the method Cancel or

CreateCancellationDocument?

Thanks and Regard.