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You’re now pretty much all set to start developing applications with awesome user interfaces. Sure, there are things that we haven’t covered yet, but the basics are all there now that you know how to work with menus, context menus, toolbars, and status bars.

The first time I came across delegates and events in C#, my mind melted. For that reason, I’ve tried really hard here to lighten the subject a little. Even so, if you are confused, it may help you to reread the chapter and also just mess around with the code.

In short, a delegate is a list of functions to call, and an event is a container for delegates. At runtime you simply create instances of delegates and add them into events. You can then call the event just as if it were a standard method, and it in turn will call every single delegate method that has been added to it.

This will open up a lot of possibilities for you when you start to design really complex systems of your own later.

To the uninitiated, generics can be a somewhat intimidating feature of C# 2.0 After all, Java only just got generics, and now C# has caught up, so obviously it’s some big and scary new high-end language feature, right? Well, no. Generics add a great deal of flexibility to C# and allow you to create type-safe collections and classes easily.

The generic collections in fact also give you a lot of flexibility in how you manage your data within your programs in an organized fashion. As you move now toward writing your own programs, you’ll find more and more use for flexible data structures such as those in the System.Collections.Generic namespace.

As you’ve seen here, working with streams, readers, and writers is easy. When you know how to use one type of stream (a file stream, for example) you really are well equipped to work with any other. Feel free to explore the various streams, readers, and writers in the online help and experiment with the code here to find out more.

I have to confess that we’ve only scratched the surface of XML support in .NET. The goal was to introduce you to the features and get you coding. There’s actually enough content and features to System.Xml to fill an entire book all its own. If you are an XML fiend, I’m sure you’ll have a ball browsing through the property and methods lists of XmlDocument, XPathNavigator, XmlReader, XmlWriter, XmlReaderSettings, and XmlWriterSettings.

In the next chapter we’ll move away from XML files as data stores and move to using fully featured SQL Server databases and the built-in database features in C# Express.

ADO.NET and database work in .NET is a massive subject, and I’ve had to make compromises in this chapter as to what I could cover. What I did cover are the basics of setting up a database, adding it to your project, and then of course using it both in code and through data binding of controls. There are whole books written on this subject, so if databases are something that fascinates you, you should definitely spend some time poring through the online help to find out more about the controls covered in this chapter. The Movie Collection starter kit application that ships with C# Express is also a great place to look for some good example code demonstrating the range of things you can do with databases and Visual C# .NET.

It’s also worthwhile reading up on the SQL Server Express online help to find all that that product can do. You can also find a lot of information on SQL Server Express online at the SQL Server Express site (http://msdn.microsoft.com/vstudio/express/sql/default.aspx).

For most of you, the ground we covered here should be more than enough to get you on the way to developing your own databases and database-driven applications.

C# Express is far more than just a desktop development tool. Armed with the WebBrowser control, the classes in the System. Net namespace, and C# Express’s excellent support for consuming remote web services, there is nothing stopping you from writing awesome applications that reach out far beyond the desktop and combine live data from sources all over the world.

The BackgroundWorker control and the Timer control provide you with a great deal of power when it comes to writing programs that seem to do more than one thing at once. Behind the scenes, the BackgroundWorker uses a bunch of .NET method calls to manage all the threading that quite frankly is pretty scary to get to grips with. The coolest part of the BackgroundWorker control is that we don’t have to deal with that nasty stuff. Anytime you want to fire up a new thread, just create an instance of the BackgroundWorker control (even in code), hook up the three events, and off you go.

I hope you’ve had fun working through this book. It was a lot of fun writing it. In this chapter I wanted to give you some pointers to online resources that can help you with the next step in your journey: creating your own applications.

Starter kits are a great stepping-stone to bigger things, giving you a working framework that you can tweak and play around with, but also giving you a full set of working code that you can explore and learn from. In addition, there are some great articles available on MSDN and through the world’s newest publishing phenomenon, blogs.

Above all else, though, remember that you aren’t alone. The community forums are there to serve not only as a reference but also as an interactive help line. Don’t be afraid to post questions to the forums when you get stuck and you’ll soon be on your way again.

Good luck, and be sure to drop me a line and let me know how you’re doing.