How to notify a user (UI) from BLL and get their response?

Question

Using VB 2008 .NET 3.5

I am working on an N-Layer desktop application.

Suppose a method in the BLL runs into an situation where the user needs to be notified and the method needs to wait for the user input (OK, Cancel, etc.) before continuing. How do you typically handle this?

Assume that this situation happens fairly often but not all the time, and is expected. It doesn't seem correct to throw an exception. The only solution I have so far is to raise an event with a custom EventArgs, and allow the UI to set some property in the custom EventArgs to reflect the user input.

Any other suggestions, or is the above technique commonly employed?

Answer 1

An event is correct.