Targeting .net framework 3.5 and 4.0 with mixed mode assembly

i have a mixed mode assem开发者_StackOverflow社区bly that targets .net 3.5 using the vc 9.0 runtime. i do wan't to support .net 4.0 yet still remain compatible to the old framework as well (the library should work for 4.0 and for 3.5 processes).

if i update to .net 4.0 i have to use the vc 10.0 runtime. however from this runtime i can't target an old .net framework anymore.

at the moment i don't see a way how to support older .net frameworks from a mixed mode assembly using the vc 10 runtime. does anyone know of a way how to accomplish this?

kind regards

Please see this link

Using Visual Studio 2010, basically you have to :

1. Manually edit the project file to add <TargetFrameworkVersion>v3.5</TargetFrameworkVersion>.
2. Use the v90 Platform Toolset.