Update: with Team Build 2013 it is easier still.

I’ve blogged before about the challenge of overriding the OutDir MSBuild property set by Team Build but this hassle is gone in version 4.5 of the .NET Framework.

I stumbled upon a change to the core Microsoft.Common.targets file while trying to understand some build issues with a work project and discovered new logic to modify the OutDir property depending on a variety of conditions. I went searching through the rest of the file for other references to OutDir and also discovered at the top of the file, a new attribute on the Project element. This new attribute’s name is “TreatAsLocalProperty” and it’s value is simply “OutDir”.

As at the time of posting this blog entry I could not find any documentation of this new functionality but based on my own testing I found that .NET Framework 4.5 now supports:

• Overriding the value of an MSBuild property that was specified at the MSBuild command-line by naming that property in the TreatAsLocalProperty attribute at the top of the build project.
• OutDir can now be specified at the command-line without a trailing slash and it will be corrected for you instead of failing the build.
• Projects can automatically build to subfolders of the Team Build drop location by setting a new MSBuild property named “GenerateProjectSpecificOutputFolder” to “true”.
• The project-subfolder will be named the same as the project file but can be overridden by specifying an alternate value for the “ProjectName” MSBuild property.
• The OutDir property can now be overridden in whatever custom way you like without modification of the Team Build workflow xaml or using a before-solution targets file.

And because .NET 4.5 is an addition to .NET 4 in the same way .NET 3.5 and .NET 3.0 were to .NET 2.0, your existing .NET 4/VS2010 projects can benefit from this new build-time functionality without taking on new run-time dependencies (with some exceptions). Here is a screenshot for how to configure Team Build 11 or a Team Build 2010 server with .NET 4.5 installed to create per-project folders in the build drop: