How to: Create a UML Diagram from Visual Studio
Using Visio for Enterprise Architects, which is included in MSDN Premium Subscription, you can create Visio UML diagrams from within Visual Studio.
To create a UML diagram from Visual Studio
Open the project you want to reverse engineer into a Visio UML diagram.
From the Project menu point to Visio UML, and then click Reverse Engineer.
Visio launches to complete the reverse engineering. You are prompted with a save dialog box where you can choose an alternative location or rename the diagram prior to saving it.