In Expression Blend 4, it's possible to load design-time resources by editing your project file. Here's an example of what that would look like:
<Page Include="Properties\DesignTimeResources.xaml"
Condition="'$(DesignTime)'=='true'
OR ('$(SolutionPath)'!='' AND Exists('$(SolutionPath)')
AND '$(BuildingInsideVisualStudio)'!='true'
AND '$(BuildingInsideExpressionBlend)'!='true')">
<Generator>MSBuild:Compile</Generator>
<SubType>Designer</SubType>
<ContainsDesignTimeResources>true</ContainsDesignTimeResources>
</Page>
Now I've been trying to get the same thing working in Visual Studio 2010 without success. Has anyone gotten design-time data to load like this in Visual Studio or is this feature only supported using Expression Blend?
You are looking for the use of d:DesignData and d:DataContext. Here is an example on Jag Reehal's blog using Blend and Visual Studio. And a Microsoft Walkthrough