David Giard MCTS, MCSD, MCSE, MCDBA Principal Consultant, Sogeti www.DavidGiard.com [email_address]

David Giard MCTS, MCSD, MCSE, MCDBA Principal Consultant, Sogeti

www.DavidGiard.com

[email_address]

Preview 2

Add classes at runtime Determine at runtime which classes to add

Add classes at runtime

Determine at runtime which classes to add

Add classes at runtime Code to interfaces Determine at runtime which classes to add Reflection

Add classes at runtime

Code to interfaces

Determine at runtime which classes to add

Reflection

Advantages Declare only class signatures Change which classes are used Disadvantage Need to reference assemblies containing classes Need to recompile if assemblies change

Advantages

Declare only class signatures

Change which classes are used

Disadvantage

Need to reference assemblies containing classes

Need to recompile if assemblies change

Advantages Read class metadata at runtime Make runtime decisions based on that metadata Disadvantage Need to load a class into memory in order to reflect on it

Advantages

Read class metadata at runtime

Make runtime decisions based on that metadata

Disadvantage

Need to load a class into memory in order to reflect on it

Add assemblies after compile? Read metadata without loading classes

Add assemblies after compile?

Read metadata without loading classes

aka “MEF”

aka “MEF”

Provide extra modules to your application, as needed Empower developers to extend your application without modifying it

Provide extra modules to your application, as needed

Empower developers to extend your application without modifying it

http://www.codeplex.com/MEF Download and unzip MEF_Preview_2_Refresh.zip Zip file contains Samples Source Code DLLs

http://www.codeplex.com/MEF

Download and unzip MEF_Preview_2_Refresh.zip

Zip file contains

Samples

Source Code

DLLs

Build Extension Create Extensible Application Set Reference to System.ComponentModel.Composition.dll Extensions Application

Build Extension

Create Extensible Application

Set Reference to System.ComponentModel.Composition.dll

Class Library Reference System.ComponentModel.Composition.dll using System.ComponentModel.Composition; [Export] attribute on class or property Metadata attributes on class or property

Class Library

Reference System.ComponentModel.Composition.dll

using System.ComponentModel.Composition;

[Export] attribute on class or property

Metadata attributes on class or property

Reference System.ComponentModel.Composition.dll using System.ComponentModel.Composition; Add “Hooks” Application

Reference System.ComponentModel.Composition.dll

using System.ComponentModel.Composition;

Add “Hooks”

[Import] attribute on property, or Code CompositionContainer container = new CompositionContainer (catalog.CreateResolver()); Catalog can be AttributedAssemblyPartCatalog DirectoryPartCatalog AggregatingComposablePartCatalog

[Import] attribute on property, or

Code

CompositionContainer container = new CompositionContainer (catalog.CreateResolver());

Catalog can be

AttributedAssemblyPartCatalog

DirectoryPartCatalog

AggregatingComposablePartCatalog

Using MEF

Using MEF

Modules for Accounting app Extensions MEFApp (Accounting) G/L A/R A/P Gen Setup

Modules for Accounting app

No recompile / redeploy No references set Extend app at runtime Examine metadata without loading

No recompile / redeploy

No references set

Extend app at runtime

Examine metadata without loading

http://www.codeplex.com/MEF David Giard, MCTS, MCSD, MCSE, MCDBA www.DavidGiard.com [email_address]

http://www.codeplex.com/MEF