managed extensibility framework 2010 01

DAVID GIARD

MCTS, MCSD, MCSE, MCDBAPrincipal Consultant, Sogetiwww.DavidGiard.comDavidGiard@DavidGiard.com

MANAGED EXTENSIBILITY FRAMEWORK

Beta 2

Compile and Deploy

TIGHT COUPLING

DLL

DLL

EXE

MEF

LOOSE COUPLING WITH MEF

Compile and Deploy

Contract

Contract

ContractContract

DLL

DLL

EXE

DLL

MANAGED EXTENSIBILITY FRAMEWORK Applications consists of loosely-coupled

components that are discovered and composed at runtime

ADVANTAGES OF MEF

Loose Coupling Swap Classes at Runtime No Recompile or Redeploy Single Plug-In Architecture

MEF USAGE SCENARIOS

Empower developers to extend your application without modifying it

Provide extra modules to your application, as needed

Use MEF as an platform ecosystem to manage all parts of your application

DEMO

MEFApp(Accounting)

G/L

A/R

A/P

Export

GenSetu

p

Modules for Accounting app

GET STARTED

MEF.CodePlex.com Download and unzip MEF_Beta_2.zip Zip file contains

DLLs Samples Source Code

DEVELOPER STEPS

Import

Export

Set Reference to System.ComponentModel.Composition.dll

Contract Import Export

Catalogs Composition

Contra

cts

MEF

CONTRACTS

[Import(“Contract1”)]String SomeThing {get; set;}

[Export(“Contract1”)]Public string SpecialThing {Get {return “A Value”};}

“A Value”

MEF

CONTRACTS

[Import(“Contract1”)]String SomeThing {get; set;}

[Export(“Contract1”)]Public string MoreSpecialThing {Get {return “A Different Value”};}

“A Different Value”

MEF

INTERFACE CONTRACTS

[Import(typeof(IFoo))]IFoo SomeFoo {get; set;}

[Export(typeof(IFoo))]public Foo: IFoo{…}

new Foo()

MEF

INTERFACE CONTRACTS

[ImportMany(typeof(IFoo))]List<IFoo> BunchOfFoos{get; set;}

[Export(typeof(IFoo))]public Foo1: IFoo{…} new Foo1()

[Export(typeof(IFoo))]public Foo2: IFoo{…} new Foo2()

COMPOSITION

Catalogs TypeCatalog AssemblyCatalog DirectoryCatalog AggregateCatalog PackageCatalog (Silverlight toolkit)

var catalog1 = new DirectoryCatalog(@"c:\MEF\Imports");var container = new CompositionContainer catalog1);container.ComposeParts(this);

DEMO

Using MEF

MEF VS DEPENDENCY INJECTION

RESOURCES http://MEF.codeplex.com http://www.davidgiard.com http://msmvps.com/blogs/kathleen http://blogs.msdn.com/gblock http://tinyurl.com/

TaultyMEFSilverlightVideos NPlus1.org

David Giard, MCTS, MCSD, MCSE, MCDBA

www.DavidGiard.comDavidGiard@DavidGiard.com

USER GROUPS

Great Lakes Area .Net User Group Southfield, MI migang.org

Greater Lansing .Net User Group East Lansing, MI glugnet.org

DAVE’S THOUGHTS

DavidGiard.com TechnologyAndFriends.com

DavidGiard@DavidGiard.com