New feature MEF in .net 4.0

Managed Extensibility Framework is the new feature of .net 4开发者_StackOverflow社区.0. What is it ? and How to use it in our existing application ?

It is a "add-in" framework which is designed to let add-ins customize a lot of things in your application. Visual Studio 2010 extension architecture is build with MEF which should give you an idea of how "extensible" it is (look at how different the extensions for VS 2010 is).

Take a look on this article:

Building Composable Apps in .NET 4 with the Managed Extensibility Framework

Description from http://code.msdn.microsoft.com/mef (which contains the source code):

The Managed Extensibility Framework (MEF) is a new library in .NET that enables greater reuse of applications and components. Using MEF, .NET applications can make the shift from being statically compiled to dynamically composed. If you are building extensible applications, extensible frameworks and application extensions, then MEF is for you.