Validation is a topic that comes up quite frequently. One concern is how to honor DRY (don't repeat yourself) principles and create a framework that is reusable across layers. There are some very robust and tested frameworks out there, but sometimes they might be more than what you are looking for. In this post, I'll show you how to build a ...

One popular gripe about Silverlight has been the lack of integrated testing tools. There are several types of tests you may perform against a software project. Unit tests can be performed with the aid of the Silverlight Unit Testing Framework and automated with a third-party tool such as StatLight. Automation testing involves hosting the actual ...

OK, so it's not exactly ''out of the box'' but the most recent PRISM 4.0 Drop (drop 2) seems to contain something Silverlight developers have been begging for ... for quite some time. It's buried within the ''QuickStart'' folder under the ''BasicMVVM'' project. This project provides guidance for the Model-View-ViewModel pattern and is worth a ...

In my last post, I showed you how to dynamically load modules on demand using the latest MEF release in Silverlight 3. This post, I will take you through managing regions with MEF. This will enable us to have a 100% MEF-based solution in Silverlight 3 if the only pieces of PRISM we were using were the dynamic module loading and region ...

Recently I've been having lots of conversations about the Managed Extensibility Framework (MEF), the Composite Application Library (CAL or PRISM), and how they relate. One point of confusion that many people has comes when they try to force the two solutions to work together. In a recent conversation, I mentioned that PRISM has some great ...

The Silverlight team recently posted a blog entry entitled ''Vancouver Olympics - How'd we do That?'' in which they detailed the massive effort across multiple partners to pull together the on-line solution for streaming HD videos, both live and on demand. This was an exciting post for Wintellect and me because it detailed the effort we ...

One reason a developer would use a technology like MEF is to, as the name implies, make an application extensible through a process called discovery. Discovery is simply a method for locating classes, types, or other resources in an assembly. MEF uses the Export tag to flag items for discovery, and the composition process then aggregates those ...

Series recap: PRISM, MEF, and MVVM Part 1 of 3: Unity GluePRISM, MEF, and MVVM Part 2 of 3: Making PRISM MEF FriendlyPRISM, MEF, and MVVM Part 3 of 3: Dynamic MEF Modules in PRISM In the final part of this series, I will show a dynamically loaded module (using PRISM) that takes full advantage of MEF. Here is a preview of the final product, ...

In the first part of this series, we explored using the Unity container to bind the view model to the view. The next logical step is to explore how to use MEF. PRISM provides several useful mechanisms that relate directly to views and modules, such as the region manager and the module manager. This allows us to dynamically assign views to regions ...

PRISM, also known as Composite WPF, has established itself as a very popular framework for building modular, scalable Silverlight applications. A newer contender, the Managed Extensibility Framework (MEF), has also grown in popularity. In fact, these two frameworks have left people scratching their heads wondering which one to use, when, how, and ...