doing your possess tradition .net eventuality guess loop

a few years ago, i review book described overrule default eventuality 'dispatcher' doing .net your possess processor.

    category foo {
       open eventuality eventhandler myevent;
       ...
    }

    ...
      myfoo.myevent += mybar1.eventhandler;
      myfoo.myevent += mybar2.eventhandler;

whenever eventuality fires, both mybar1 mybar2 handlers called.

as i recall, default doing loop uses related list simply iterates over list calls eventhandler representatives order.

my doubt twin fold:

1. does someone know book i reading?


2. why wish overrule default doing (which competence answered book)?

edit: book i referring indeed jeffrey richter's clr around c#