Migrating from .NET 1.1 to .NET 3.5

Question

What would be some compelling reasons to upgrade a web app from .NET 1.1 to .NET 3.5?

Answer 1

The question isn't 'whether you should',-- in terms of features and added compile-time checks; it's almost a given to get out of the 1.1 framework and into the 2.0 framework. The question is, how fast should you port? What would need to be changed?

Your first step would be to port your application to .NET 2.0. The reason is is that there are plenty of features in .NET 2.0 that didn't exist before, and previous features were deprecated. (In ASP.NET, there were a slew of features deprecated in 2.0).

.NET 2.0 allows for stronger type-safety, nullable types, and changes in the framework. 2.0 represents (what I would consider) the first 'real' release of the .NET platform. It is a serious contender, and you'll find that some of the framework stuff you use in 1.1 has been modified in 2.0.

It's not a simple 'port the code forward and get the benefits' scenario. If you want the benefits, you'll have to rewrite some code (most notably, things involving Generics); but even in the larger .NET framework, there are so many 'behind the scenes changes' that you'll want to port it incrementally: Don't make the jump directly from 1.1 - 3.5.

1.1 - 2.0

• Generics
  
• Static Classes
  
• Nullable Types
  
• Yield Operator
  
• Property Access Modifiers
  
• Partial Types
  
• Aliases

There are a slew of changes between .NET 2.0 and .NET 3.0. There was an entire paradigm shift. (Though admittedly it is a voluntary shift). Wikipedia has an entire section devoted to it, but I'll (some!) of the changes here:

.NET Framework changes

• Windows Presentation Foundation (WPF)
• Windows Communication Foundation (WCF)
• Windows Workflow Foundation
• Windows CardSpace

C# Changes:

• LINQ
• Object Initalizers
• Collection Initalizers
• Anonymous Types
• Lambda Expressions
• Automatic Properties
• Extension Methods (Source: Wikipedia)

More to come, obviously. Just the jump from 1.1 to 2.0 is worth an entire release cycle.

Answer 2

.net 1.1 is deprecated, not being further developed. i'm not sure about security issues. but in general, it's abandoned, and as of 2.0 microsoft ensures back-compatibility in newer versions which isn't the case to 1.1.

so if you have a chance to move - move. you get new language features, you get a framework being constantly built further and further. you get linq if you need it, silverlight support, generics of course, etc.

Answer 3

I've actually recently finished converting an entire code-base from .NET 1.1 to .NET 2.0. Take into account that .NET 3.5 is actually just sets of extensions for .NET 2.0, it's not a completely new base.

The difference is really quite substantial in many parts. To me, .NET 1.1 had not been "tamed" in any way whatsoever, and required an awful amount of code. Furthermore, VS 7 had to be used against .NET 1.1, so older tools were required.

For web apps a different web config was required as it exposes the .NET version which made it even messier. Don't get into the ".NET 3.5 has new features therefore I must move to it" motion, because you have to make the decision based on requirements, not on potential tool uses. As many-an-author rightly points out, there's a good chance you won't use half of the features that compose the entire framework.

I would recommend, on the other hand, to shift from .NET 1.1 to .NET 2.0 at least.