SharePoint 2010 Solutions using .NET 4.5

Question

I am creating a solution (wsp file) that will be installed on a SharePoint 2010 Server. The solution uses a third party DLL which was built on .NET 4.5. I have created my solution using the target framework of .NET 4.5 to accommodate this third party DLL, but I am not able to add the solution as SP 2010 is based on .NET 3.5. Is there an update to SP2010 that will allow for .NET 4.5 based solutions?

Saul

Answer 1

Well kind of, that upgrade is SharePoint 2013.

In your case you're probably best off splitting you solution into two:

• a seperate web service or windows service using 4.5 which hosts the dll
• the wsp part in 3.5 calling this service

Answer 2

SharePoint 2010 does not support access from .NET Framework 4 or being run in a .NET Framework 4 app domain. If you must support the .NET Framework 4, we recommend that you develop a web service that uses the .NET Framework 4 and then connect to it from SharePoint. All server-side customizations directly for SharePoint 2010 still need to be either the .NET Framework 3.5 or the .NET Framework 3.5 SP1.

For more information, see the following MSDN Library topics.

• Requirements for Developing SharePoint Solutions
• How to: Set the Correct Target Framework and CPU

Source: NET Framework support in SharePoint 2010