CSharpDev

Migrating from Visual Studio 2010 beta 1 to beta 2 – solution file change required

By jonskeet

Having installed Visual Studio 2010 beta 2 on my freshly-reinstalled netbook (now with Windows 7 and and SSD – yummy) I found that my solution file from Visual Studio 2010 beta 1 wasn’t recognised properly: double-clicking on the file didn’t do anything. Opening the solution file manually was absolutely fine, but slightly less convenient than being able to double-click. After a bit of investigation, I’ve found the solution. Manually edit the solution file, and change the first few lines from this: Microsoft Visual Studio Solution File, Format Version 11.00 # Visual Studio 10 to this: Microsoft Visual Studio Solution File, … Continue reading Migrating from Visual Studio 2010 beta 1 to beta 2 – solution file change required

For vs Foreach on arrays and lists

By jonskeet

As promised earlier in the week, here are the results of benchmarking for and foreach. For each of int and double, I created an array and a List<T>, filled it with random data (the same for the list as the array) and ran each of the following ways of summing the collection: A simple for loop, testing the index against the array length / list count each time A for loop with an initial variable remembering the length of the array, then comparing the index against the variable each time A foreach loop against the collection with the type known … Continue reading For vs Foreach on arrays and lists

Benchmarking made easy

By jonskeet

While I was answering a Stack Overflow question on the performance implications of using a for loop instead of a foreach loop (or vice versa) I promised to blog about the results – particularly as I was getting different results to some other posters. On Saturday I started writing the bigger benchmark (which I will post about in the fullness of time) and used a technique that I’d used when answering a different question: have a single timing method and pass it a delegate, expected input and expected output. You can ask a delegate for the associated method and thus … Continue reading Benchmarking made easy

Designing LINQ operators

By jonskeet

I’ve started a small project (I’ll post a link when I’ve actually got something worthwhile to show) with some extra LINQ operators in – things which I think are missing from LINQ to Objects, basically. (I hope to include many of the ideas from an earlier blog post.) That, and a few Stack Overflow questions where I’ve effectively written extra LINQ operators and compared them with other solutions, have made me think about the desirable properties of a LINQ operator – or at least the things you should think about when implementing one. My thoughts so far: Lazy/eager execution If … Continue reading Designing LINQ operators

You don’t have to use query expressions to use LINQ

By jonskeet

LINQ is clearly gaining a fair amount of traction, given the number of posts I see about it on Stack Overflow. However, I’ve noticed an interesting piece of coding style: a lot of developers are using query expressions for every bit of LINQ they write, however trivial. Now, don’t get the wrong idea – I love query expressions as a helpful piece of syntactic sugar. For instance, I’d always pick the query expression form over the “dot notation” form for something like this: var query = from file in Directory.GetFiles(logDirectory, “*.log”)            from line in new LineReader(file)            let entry = new LogEntry(line)            … Continue reading You don’t have to use query expressions to use LINQ

Value types and parameterless constructors

By jonskeet

There have been a couple of questions on StackOverflow about value types and parameterless constructors: Structure vs Class in C# Why can’t I define a default constructor for a struct in .NET I learned quite a bit when answering both of these. When a further question about the default value of a type (particularly with respect to generics) came up, I thought it would be worth delving into a bit more depth. Very little of this is actually relevant most of the time, but it’s interesting nonetheless. I won’t go over most of the details I discovered in my answer … Continue reading Value types and parameterless constructors

Redesigning System.Object/java.lang.Object

By jonskeet

I’ve had quite a few discussions with a colleague about some failures of Java and .NET. The issue we keep coming back to is the root of the inheritance tree. There’s no doubt in my mind that having a tree with a single top-level class is a good thing, but it’s grown a bit too big for its boots. Pretty much everything in this post applies to both .NET and Java, sometimes with a few small changes. Where it might be unclear, I’ll point out the changes explicitly – otherwise I’ll just use the .NET terminology. What’s in System.Object? Before … Continue reading Redesigning System.Object/java.lang.Object

The Snippy Reflector add-in

By jonskeet

Those of you who’ve read C# in Depth will know about Snippy – a little tool which makes it easy to build complete programs from small snippets of code. I’m delighted to say that reader Jason Haley has taken the source code for Snippy and built an add-in for Reflector. This will make it much simpler to answer questions like this one about struct initialization, where you really want to the IL generated for a snippet. Here’s a screenshot to show what it does: This is really cool – if you want to dabble to see what the C# compiler … Continue reading The Snippy Reflector add-in

Copenhagen C# talk videos now up

By jonskeet

The videos from my one day talk about C# in Copenhagen are now on the MSDN community site. There are eight sessions, varying between about 25 minutes and 50 minutes in length. I haven’t had time to watch them yet, but when I do I’ll submit brief summaries so you can quickly get to the bits you’re most interested in. (As far as I’m aware, they’re only available via Silverlight, which I realise isn’t going to be convenient for everyone.) Feedback is very welcome.

.NET 4.0’s game-changing feature? Maybe contracts…

By jonskeet

Update: As Chris Nahr pointed out, there’s a blog post by Melitta Andersen of the BCL team explaining this in more detail. Obviously I’ve been looking at the proposed C# 4.0 features pretty carefully, and I promise I’ll blog more about them at some later date – but yesterday I watched a PDC video which blew me away. As ever, a new version of .NET means more than just language changes – Justin van Patten has written an excellent blog post about what to expect in the core of thee framework. There are nice things in there – tuples and … Continue reading .NET 4.0’s game-changing feature? Maybe contracts…