Upgrading Code from .Net 1.1 to 2.0/3.5 (C#)

Question

I am upgrading a Windows Client application that was earlier .NET 1.1. The previous developer handwrote many solutions that can be done automatically with the newer versions of .NET. Since I am relatively fresh to .NET and do not have the complete overview of the features I am asking here.

What is the most notable classes and syntax features provided in later .NET versions that is likely to swap out handwritten code with features from the library?

Answer 1

LINQ was a big leap. Might be possible to use that in some places (e.g. XML code). Also, generics may reduce the need for some classes.

Answer 2

Biggest changes off the top of my head:

• Use generic collections instead of ArrayList, Hashtable etc.
• For C# 3.5, use LINQ instead of manually filtering/projecting
• Use generic delegates instead of having to declare your own all the time
• Use anonymous methods instead of creating a one line method used to create a delegate in one place
• Use BackgroundWorker for WinForms background tasks

Generics is the most wide-reaching change in my view.

Answer 3

Personally, I would leave any 1.1 code that works fine when compiled with 2.0/3.5. Unless you have the time, anything you rewrite you'll have to test again, and you still may introduce new bugs that your testing can't find.

Things that I'd look to use for future versions though, would be generics and LINQ. Generics with .NET 2, and LINQ with .NET 3.5.

Answer 4

Also be aware of and test for possible impact of breaking changes between the versions of the framework. A google search should reveal the top issues.