VS loads the project once and then saves it in memory. If you want to build two assemblies from VS, you can add an AfterBuild target and call MSBuild to build the assembly again, but with different parameters:
<ProperttyGroup Condition="'$(BuildAgain)'==''"> <!-- Default parameters to VS --> <AssemblyName>Name1,Default</AssemblyName> <ProperttyGroup> <ProperttyGroup Condition="'$(BuildAgain)'=='true'"> <!-- Overrided parameters --> <AssemblyName>Name2.Custom</AssemblyName> <ProperttyGroup> <Target Name="AfterBuild" Condition="'$(BuildAgain)'==''"> <MSBuild Projects="$(MSBuildProjectFullPath)" Properties="BuildAgain=true;Configuration=$(Configuration);Platform=$(Platform)" Targets="Rebuild" </Target>
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