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MEF in .NET 3.5 ???

Apr 29, 2010 at 7:03 AM
Hi all, I m considering to use MEF for a project in my company. However, we're still using .NET 3.5 .. Is there any chance i can use a MEF release targetting this version of the fwk ??? Tks Fabien
Apr 29, 2010 at 7:26 AM

Hi Fabien

MEF's codeplex source is 3.5. The version we ship in the framework is .NET 4.0.

The source is released under MSPL and you are free to use it.



Apr 29, 2010 at 9:20 AM

Thanks for the answer Glenn. I am pretty excited about the possibilities of MEF; yet, as a perfect newbie, I have a couple more questions :

1- How does MEF deal with security ? I mean, is there any way to "activate" a part in a separate security context / app domain ?

2- How does MEF deal with backward/forward compatibility between host and parts ?

Thanks in advance for the time you take to answer my questions,



May 6, 2010 at 7:23 PM

Fabien, is Preview 9 essentially the same as the release?  (i.e., is there another release we should be waiting for to use in .NET 3.5 projects). 

May 6, 2010 at 8:03 PM

Yes, essentially the same. For future releases we will probably target .net 4.0

May 6, 2010 at 8:05 PM


1. MEF doesn't do anything related to security. If you need sandboxing, currently, you have to code that yourself.

2. Versioning is also something that MEF doesn't address directly. You'd have to plan/design a strategy yourself. We're evaluating options for the next release, though.

May 7, 2010 at 6:20 AM
Thanks Haveriss !