When is useful to use delegate type in a web application

I use C# and Asp.Net Web Forms.

I read about the way Asp.Net deal with events for the GUI Objects using its "Delegate Model".

I'm concerting if would make sense use "Custom Delegate Type" in other context a part of event handling.

My questions:

• In a real world scenario when could be useful to use Delegate Types apart from event handling? Example: for validation fields in a class?

• In which kind of architecture Custom Delegate Type best feet?

• Pro an开发者_开发知识库d Cons of Delegate Type?

Thanks for your time on this!

• If you use LINQ to Objects at all, you're using delegates. (If you're using EF or something similar, then you're using expression trees of delegate types.)

• If you use MVC, you're probably using expression trees too (@Html.For(x => ...))

• If you ever start threads or tasks, you'll be using delegates.

Basically they're great for representing single operations in an easily-expressible way. They can be used as an alternative to single-method interfaces, and work well for providing hooks for custom behaviour instead of using inheritance.

Since .NET 3.5 with its Action and Func delegate families, I rarely create custom delegate types - only when it makes sense to do so on readability grounds, basically.