This packages provides a version of the Managed Extensibility Framework (MEF) that is lightweight and specifically optimized for high throughput scenarios, such as the web.
Supported Platforms:
- .NET Framework 4.5
- Windows 8
- Windows Phone 8.1
- Windows Phone Silverlight 8
- Portable Class Libraries
To install Microsoft Composition (MEF 2), run the following command in the Package Manager Console
PM> Install-Package Microsoft.Composition
Requires NuGet 2.5 or higher.
原文：http://www.cnblogs.com/zjoch/p/4583896.html