Mrs. Simpson

With contributions by Nicolas Botto, Bob Brumfield, Grigori Melnik, Erik Renaud, Fernando Simonazzi, Chris Tavares

RELEASE CANDIDATE 6/7/2010

Copyright
This document is provided “as-is”. Information and views expressed in this document, including URL and other Internet Web site references, may change without notice. You bear the risk of using it. Some examples depicted herein are providedfor illustration only and are fictitious. No real association or connection is intended or should be inferred. This document does not provide you with any legal rights to any intellectual property in any Microsoft product. You may copy and use this document for your internal, reference purposes. You may modify this document for your internal, reference purposes © 2010 Microsoft. All rightsreserved. Microsoft, Visual Studio, and Windows are trademarks of the Microsoft group of companies. All other trademarks are property of their respective owners.

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Developer's Guide to Microsoft Enterprise Library 5.0 (Release Candidate)

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Foreword
You are holding in your hands a book that will make your life as an enterprise developer a whole lot easier. It’s a guide on MicrosoftEnterprise Library and it’s meant to guide you through how to apply .NET for enterprise development. Enterprise Library, developed by the patterns & practices group, is a collection of reusable components, each addressing a specific cross cutting concern—be it system logging, or data validation, or exception management. Many of these can be taken advantage of easily. These components are architectureagnostic and can be applied in a multitude of different contexts. The book walks you through functional blocks of the Enterprise Library, which include data access, caching, cryptography, exception handling, logging, security, and validation. It contains a large collection of exercises, tricks and tips. Developing robust, reusable and maintainable application requires knowledge of design patterns,software architectures and solid coding skills. We can help you develop those skills with Enterprise Library since it encapsulates proven and recommended practices of developing enterprise applications on the .NET platform. Though this guide does not go into the depth of discussions of architecture and patterns, it provides a solid basis for you to discover and implement these patterns from areusable set of components. That’s why I also encourage you to check out the Enterprise Library source code and read it. This guide is not meant to be a complete reference on Enterprise Library. For that, you should go to MSDN. Instead, the guide covers most commonly used scenarios and illustrates how Enterprise Library can be applied in implementing those. The powerful message manifesting from theguide is the importance of code reuse. In today’s world of complex large software systems, high-quality pluggable components are a must. After all, who can afford to write and then maintain dozens of different frameworks in a system—all to accomplish the same thing? Enterprise Library allows you to take advantage of the proven code complements to manage a wide range of task and leaves you free toconcentrate on the core business logic and other “working parts” of your application. Another important emphasis that the guide makes is on software designs, which are easy to configure, testable and maintainable. Enterprise Library has a flexible configuration subsystem driven from either external config files or programmatically or both. Leading by example, the Enterprise Library itself is designedin a loosely-coupled manner. It promotes key design principles of the separation of concerns, single responsibility principle, principle of least knowledge and the DRY principle (Don’t Repeat Yourself). Having said this, don’t expect this particular guide to be a comprehensive reference on design patterns. It is not. It provides just enough to demonstrate how key patterns are used with...