The dialog is being started from DialogContext.beginDialog or DialogContext.replaceDialog.
The dialog is being cancelled from DialogContext.cancelAllDialogs.
The dialog is being continued from DialogContext.continueDialog.
The dialog is being ended from DialogContext.endDialog.
A step in a WaterfallDialog is being called because the previous step in the waterfall dialog called WaterfallStepContext.next.
The dialog is being ended from DialogContext.replaceDialog.
Indicates why a dialog method is being called.
Remarks
Use a dialog context to control the dialogs in a dialog set. The dialog context will pass a reference to itself to the dialog method it calls. It also passes in the reason why the specific method is being called.