Question

I feel that I am not utilizing all the features of delegates/events available in .NET 3.5 and beyond. And more or less still using delegates power available in 2.0. I would appreciate if you tell me how delegates/events should be used now, tricks, short-cuts.

Thanks.

EDIT

Jon suggested his publication on this subject, and I am posting here for easier navigations:

A few of my articles which may be relevant:

• Events
• Delegates in C# 2.0
• Closures
• C# 2 bluffers’ guide
• C# 3 bluffers’ guide

My book, C# in Depth, has a whole chapter devoted to delegates (chapter 5). Unfortunately that’s not one of the free ones 🙁

ps. I couldn’t find a duplicate of this question but did look through many on this theme.

Answer 1

A few of my articles which may be relevant:

• Events
• Delegates in C# 2.0
• Closures
• C# 2 bluffers’ guide
• C# 3 bluffers’ guide

My book, C# in Depth, has a whole chapter devoted to delegates (chapter 5). Unfortunately that’s not one of the free ones 🙁

The main changes in summary (as Jared said, these are language changes – .NET itself hasn’t changed much beyond them becoming generic, and the framework supplying the handy Func and Action delegates):

C# 2:

• Method group conversions:

  // Old: button.Click += new EventHandler(HandleClick); // New: button.Click += HandleClick; 

• Anonymous methods:

  button.Click += delegate { Console.WriteLine('Click!'); }; 

• Covariance/contravariance:

  EventHandler generalHandler = LogEvent; button.Click += generalHandler; button.KeyPress += generalHandler; // Event type is KeyPressEventHandler 

C# 3:

• Lambda expressions:

  button.Click += (sender, args) => Console.WriteLine('Click!'); 

  or more importantly:

  var people = list.Where(person => person.Name != 'Jon')                  .OrderBy(person => person.Age);