Patterns Practices(.Net)

The Patterns & Practices team at Microsoft provides a collection of resources to help developers apply best practices to the development, deployment and
operation of enterprise applications. Guidance comes in four primary forms: Software Factories, Application Blocks (including Enterprise Library), Reference
Implementations and Guidelines.
Software Factories are configurable tools your architects and developers use to build applications. Application Blocks are reusable application components that implement software design patterns and are built with best practices for enterprise use.
Reference Implementations are full, working applications that you can use as a starting point for your own applications, or simply use as examples.
Guidelines appear as architectural and prescriptive guidance (wizards, how-tos, and documentation).
The Patterns & Practices code is available in source form so you can extend it, and there are active developer communities around many of the tools that
offer additional guidance and support. Start using the tools today, join the communities, and become more productive as an architect and/or developer!
Web Client Software Factory (WCSF), Smart Client Software Factory (SCSF)Web Service Software Factory (WSSF)
Smart Client Software Factory (SCSF):Architects and developers can quickly incorporate many of the proven practices and patterns of building composite smart client applications. These practices
and patterns have been identified during the development of many smart client applications and their components.
By using the software factory, architects and developers can focus their efforts on business opportunities and create smart client applications that
effectively address the needs of their organizations.
The Smart Client Software Factory provides an integrated set of guidance that assists architects and developers create composite smart client applications.
These applications have one or more of the following characteristics:
They have a rich user interface that takes advantage of the power of the Microsoft Windows desktop. They connect to multiple back-end systems to exchange data with them. They present information coming from multiple and diverse sources through an integrated user interface, so the data looks like it came from one back-end
system. They take advantage of local storage and processing resources to enable operation during periods of no network connectivity or intermittent network
connectivity. They are easily deployed and configured.
This software factory provides proven solutions to common challenges found while building and operating composite smart client applications. It helps
architects and developers build modular systems that can be built and deployed by independent teams. Applications built with the software factory use proven
practices for operations, such as centralized exception logging.
The software factory contains a collection of reusable components and libraries, Visual Studio 2008 solution templates, wizards and extensions, How-to
topics, automated tests, extensive architecture documentation, patterns, and a reference implementation. The software factory uses Windows Forms, Windows
Presentation Foundation, Windows Communication Foundation, and the Enterprise Library 3.1 – May 2007 release. With this release, the Composite UI Application
Block is included in the software factory
******************************************Web client applications and their components:
These applications have one or more of the following characteristics:
They are developed by multiple collaborating development teams. They are composite applications that present information from multiple sources through an integrated user interface. They support XCopy deployment of independently developed modules. They support online business transaction processing Web sites. They deliver a responsive user experience. Note The software factory is optimized to create online business transaction processing Web sites. It is not optimized for Web content sites or collaboration
sites.
This software factory provides proven solutions to common challenges found while building and operating large transaction processing enterprise Web sites. It
helps architects and developers build modular systems. A module is a functionally complete and independent component. Modularity allows independent teams to
work on different aspects of the application and also improves security and testability. Applications built with the software factory use proven practices
for operations like centralized exception logging and can be XCopy deployed.
The software factory contains a collection of reusable components and libraries, Visual Studio 2008 solution templates, wizards and extensions, How-to
topics, automated tests, extensive architecture documentation, patterns, and a reference implementation. The software factory uses ASP.NET, ASP.NET AJAX, the
AJAX Control Toolkit, and the Enterprise Library
*******************Application Blocks-(Enterprise Library)
Caching Application Block. Developers can use this application block to incorporate a local cache in their applications. Cryptography Application Block. Developers can use this application block to incorporate hashing and symmetric encryption in their applications. Data Access Application Block. Developers can use this application block to incorporate standard database functionality in their applications. Exception Handling Application Block. Developers and policy makers can use this application block to create a consistent strategy for processing exceptions
that occur throughout the architectural layers of enterprise applications. Logging Application Block. Developers can use this application block to include standard logging functionality in their applications. The Policy Injection Application Block. Developers can use this application block to implement interception policies that streamline the implementation of
common features, such as logging, caching, exception handling, and validation, across an application. Security Application Block. Developers can use this application block to incorporate authorization and security caching functionality in their applications. Unity Application Block. Developers can use this application block to implement a lightweight, extensible dependency injection container with support for
constructor, property, and method call injection. The Validation Application Block. Developers can use this application block to create validation rules for business objects that can be used across different
layers of their applications.
Design-time configuration classes that support the configuration tools and allow developers to specify and persist configuration information for the library
and the application blocks Run-time configuration classes and providers that expose configuration data to the library, the application blocks, and users' applications at run time Common utility functions for tasks such as serialization, used in many places throughout the library and the application blocks and available for developers
to use in their code Instrumentation features that allow developers and administrators to monitor the behavior and performance of the application blocks at run time
Composite UI Application Block:
The application block is designed to support the development of smart client line-of-business applications such as the ones found in the following scenarios:
Online transaction processing (OLTP) front-ends, in areas such as stock distribution centers or data entry applications Rich client portals to back-end services, such as portals to government services or bank teller applications UI intensive information-worker standalone applications, such as those used by call center staff, IT support desks, or stock traders All these scenarios require rich user interaction, a shell architecture that can host the user interface and business logic "parts," and varying degrees of
centralized control of the functionality and behavior that the application exposes to its users.
The Composite UI Application Block facilitates the design and implementation of your client applications in three areas:
It allows your application to be based on the concept of modules or plug-ins. It allows developers with shell expertise to build components that hide user interface complexity from the business logic development. It facilitates development using patterns for loose coupling between modules.
For example you are devloping call center application. In this call center application, the main screen is built using multiple collaborating parts, each one
addressing a specific aspect of a business process (for example, billing, claims, or customer information). All of these parts could potentially be developed
by different teams. The parts may interact with different back-end systems and can be independently versioned, deployed, and updated. However, they are
integrated to provide a consistent user experience, share information between each other, and communicate to help the end user complete a specific task.
Shell developers are responsible for building the components that give this application its custom, yet consistent, appearance and behavior (look and feel).
The Composite UI Application Block implements the underlying architecture that helps build these types of applications.
Reference Implementation:
(1) Developed concurrently with spec and test suite;(2) Verifies that specification is implementable;(3) Enables the test suite to be tested;(4) Serves as Gold Standard against which other implementations can be measured; (5) Helps to clarify intent of specification where conformance tests are
inadequate