1. How and When to Use MEF: Too Much Is Never Enough
Tech Ed North America 2010
5/4/2019 8:35 PM
SESSION CODE: DEV304
How and When to Use MEF: Too Much Is Never Enough
Jon Flanders
Title
MCW Technologies
© 2010 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

2. Managed Extensibility Framework (MEF)
MEF is a framework for creating loosely-coupled, extensible applications
This has always been possible with .NET
Interfaces+classes+dynamic assembly loading
MEF is a standardization of this pattern
Much of Visual Studio 2010 uses MEF
Its extensibility layer relies on it heavily

3. MEF in a nutshell MEF centers around three main concepts
Catalog
Exports
Imports
Catalogs contain components that are to be composed
Exports expose “Contracts”
Classes or properties
Imports are properties that require Exported instances
Composition pulls it all together

4. Tech Ed North America 2010 Name Title Company
5/4/2019 8:35 PM
MEF in action
Name Title Company
DEMO
© 2010 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

5. MEF Basics…
Export it.
Import it.
Compose it.

6. Widget1 Export it. Export UserControl [Export(typeof(UserControl))]
public class Widget1 : UserControl {
public string Message {
get{return(string) Button.Content;}
set{Button.Content=value;} }
Widget1
UserControl
Export

7. Widget1 Import it. Import String [Export(typeof(UserControl))]
public class Widget1 : UserControl {
[Import]
public string Message {
get{return(string) Button.Content;}
set{Button.Content=value;} }
Widget1
String
Import

8. Widget1 Import it. Import “HelloMEF.Message”
[Export(typeof(UserControl))]
public class Widget1 : UserControl {
[Import(“HelloMEF.Message”)]
public string Message {
get{return(string) Button.Content;}
set{Button.Content=value;} }
Widget1
“HelloMEF.Message”
Import

9. Main Page Import it. ImportMany UserControl
[Export(typeof(UserControl))]
public class MainPage: UserControl {
[ImportMany(typeof(UserControl))]
public IEnumerable<UserControl> {
get;set; }
Main
Page
UserControl
ImportMany

10. PartIntializer: “Compose yourself”
Compose it.
PartIntializer: “Compose yourself”
public MainPage() {
InitializeComponent();
CompositionInitializer.SatisfyImports(this); }
Main Page
Compose

11. Tech Ed North America 2010 Name Title Company
5/4/2019 8:35 PM
MEF in an application
Name Title Company
DEMO
© 2010 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

12. Resources Learning www.microsoft.com/teched www.microsoft.com/learning
Tech Ed North America 2010
5/4/2019 8:35 PM
Resources
Learning
Sessions On-Demand & Community
Microsoft Certification & Training Resources
Resources for IT Professionals
Resources for Developers
© 2010 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

13. Related Content Interactive Sessions
Tech Ed North America 2010
5/4/2019 8:35 PM
Related Content
Interactive Sessions
DEV05-INT | What's Wrong with My .NET Extensible MEF Application?
Session Type: Interactive Session
Thursday, June 10 | 8:00 AM - 9:15 AM | Rm 347
Track: Developer Tools, Languages & Frameworks
Speaker(s): Daniel Plaisted
Level: Advanced
Hands-on Labs
DEV06-HOL | Introduction to Managed Extensibility Framework
© 2010 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

14. Complete an evaluation on CommNet and enter to win!
Tech Ed North America 2010
5/4/2019 8:35 PM
Complete an evaluation on CommNet and enter to win!
© 2010 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

15. Tech Ed North America 2010 5/4/2019 8:35 PM
© 2010 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.
© 2010 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

16. Required Slide Tech Ed North America 2010 5/4/2019 8:35 PM
© 2010 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.