This book is not a treatment of the theory of design patterns. We show design patterns applied in real-world architectural scenarios so that you can see them in action and see the benefits that they bring. It explains why it's worth spending time building design patterns into your applications, even though this may seem at odds with Rapid Application Development. After a fast-paced introduction to design patterns, the core of this book consists of three case studies, which show how design patterns are applied in each of the main tiers of an application: the data, business, and presentation layers. These case studies flesh out the reader's understanding of design patterns, and show how they can be employed in real scenarios that will be instantly recognizable to all VB .NET programmers. The book also shows how design patterns can be used in conjunction with .NET Remoting, so that they can be applied not just within individual tiers, but across them as well. Since many VB .NET programmers may not be completely familiar with UML, we also provide a UML primer as an appendix.

Dynamic Language Runtime (DLR) in .NET is a framework for designing and interacting with dynamic languages such as Python and Ruby. For the first time, the DLR places such languages on an equal footing in the .NET world with compiled languages such as C# and VB.NET. Chaur Wu's book, Pro DLR in .NET 4, introduces you to this important new framework, helping you to take practical advantage of the DLR in your day-to-day work. Pro DLR in .NET 4 begins with the fundamentals of the DLR, showing how they work to provide interoperability support for dynamic languages. You'll learn to mix and match objects and functions from compiled and dynamic languages such as C# and Python, allowing you to take advantage of the right tool at the right time for the right task. The DLR also brings new flexibility and possibility to your software application design. Pro DLR in .NET 4 shows you how to host dynamic languages in your application, enabling users to write scripts to automate tasks. You'll understand the meta-object protocol and meta-programming capabilities. These reside at the core of DLR, bringing new possibilities to the design and architecture of .NET applications.* Comprehensive coverage of an important new .NET technology * Meets the needs of programmers wanting to apply dynamic languages such as Python and Ruby in their .NET solutions * Assists language developers in supporting their languages under .NET.What you'll learn* Mix and match dynamic and compiled code in your applications.* Run Python, Ruby, PHP, and other dynamic code with full access to .NET functionality.* Create domain-specific languages for use in your own applications.* Host dynamic languages and provide scripting capability in your applications.* Learn and apply the concepts of meta-programming and meta-object protocol.* Streamline and automate unit-testing through scripts written in dynamic languages.Who this book is for Pro DLR in .NET 4 is for any .NET programmer wanting to benefit from the new ability of dynamic languages such as Python and Ruby to function as first-class citizens in a .NET environment. It's a book for those wishing to mix and match dynamic and static languages in ways that improve programmer and user productivity. It's also a book for those implementing domain-specific languages, who wish to add scripting capabilities to their applications.