You can get the PowerPoint slides and the demo code from here. Technorati Tags: .NET, WPF

Tomorrow I'll do a presentation about WPF in the Microsoft Dreamway event in Lisbon, at Centro Cultural de Belém. My session will be Dev09 at 17:30. Check out the agenda. Technorati Tags: .NET, WPF

After you start to use extension methods and see all their benefits, you start thinking about how nice it would be to also have extension properties. When Scott Guthrie first announced them in New "Orcas" Language Feature: Extension Methods, someone immediately asked about extension properties. It just seems the feature is incomplete without both. One particular area that would benefit greatly from extension properties would be WPF. Every time you define an attached property, you usually create a static getter and a static setter for it. If you could package that up in an extension property, attached properties would be much...

Updated on 2008/09/17: Fixed problem when skipping elements. Updated on 2008/09/15: Fixed problem when trying to read missing attributes. One of new features introduced in .NET 3.5 that I welcomed the most was LINQ to XML. The old DOM API was a bit clumsy to use, and the simple fact that you don't need owner documents any more makes the new XElement much more flexible and pleasant to work with than the old XmlElement. Also new is an API for streaming XML output, XStreamingElement, that by using deferred execution gives you SAX-like performance on a DOM-like API. There's no streaming XML input...

Did you know that the Avalon project (the original name of WPF) was started back in 2001, even before .NET Framework 1.0 was released, from the team that originally developed Internet Explorer 4 DHTML support and the XMLHttpRequest API that enables AJAX? I've learned that and some other interesting trivia from this Channel 9 video: Michael Wallent: Advent and Evolution of WPF Technorati Tags: .NET, WPF

I've been lately looking at some channel 9 videos, and found a lot of great stuff there. Two that I found particularly interesting were these: Expert to Expert: Contract Oriented Programming and Spec# Ted Neward: On Java and .NET, Software Academics versus Practioners, General Purpose Programming Languages Technorati Tags: .NET

Can Erten created a very useful expression tree to CodeDom converter. He wrote about it here: Expression Trees-Lambdas to CodeDom Conversion. I created a visual studio debugger visualizer based on it. You can find it in attachment. Just copy the assembly to My Documents\Visual Studio 2008\Visualizers and you're set. I also attached the full source code. ExpressionCodeDomVisualizer.dll ExpressionCodeDomVisualizerSourceCode.zip Technorati Tags: .NET, LINQ

Expression trees are one of the more powerful features of C#. They let you manipulate code in ways that almost remind you of LISP macros (but at runtime instead of compile time). Since I discovered them, I managed to eliminate almost completely the usage of reflection in my code, replacing it with much faster code using techniques similar to what Roger Alsing described in Linq Expressions - Creating objects. Expression trees also made possible something that I find myself using a lot these days: what Jomo Fisher described in Fast Switching with LINQ. It's a great example of the powerful...

.NET includes a managed MSMQ API (System.Messaging) to send and receive messages, but unfortunately there's a key functionality missing: obtaining the number of messages currently in the queue. Yoel Arnon talks about this problem with more detail here and here. After reading that, we learn that there are three ways to overcome this limitation: using the MSMQ performance counters (with the .NET Performance Counter API or via WMI), using the MSMQ COM wrapper, or using the MSMQ Admin API directly. The first option is not very reliable and the second one is not available on all versions of MSMQ, so...