Projection - MerrionComputing/CQRSAzure GitHub Wiki

A projection is a function that runs over an aggregate instance's event stream and for each event that it encounters, if the projection is set to handle that event type, updates its internal properties according to the existence or the properties of the given handled event.

A projection can be run up until a given point in time or up to the most recent topmost event in the stream to give the "as of now" value.

In the CQRS Designer we can make a projection handle a particular event by connecting it to the event. In the generated code this will create a HandleEvent method for that event.