Does expression and Visual Studio mix WPF control rendering differently

Question

In my WPF application, I created a form using Expression Blend. To my surprise, the rendering is completely different when I load the solution using Visual Studio 2008. Even more surprisingly, when I launch the application, the resulting user interface is different from the rendering done by both VS and Blend. Although I did not provide the XAML code, but overall is this a known issue?

Answer 1

This is definitely a known issue. Visual Studio uses what is called the Cider designer to render WPF code. This definitely makes XAML different than Blend. The cider in VS2008 is pretty awful, but in 2010 it gets a lot better (but still pretty awful compared to Blend). One of the main differences between Cider and Blend is that Cider will read the code behind the file (* .xaml.cs), while Blend will completely ignore it. Another notable difference is that Cider really doesn't understand things like Visual States and the Blend SDK Behaviors (especially when you mix them), while Blend understands them completely.

If you create view classes where you set your DataContext in XAML and then provide development-time data (using Blend or a view model locator), you will find that runtime is looking between Blend and some.