The patterns & practices group at Microsoft provides architectural and design guidance for users of Microsoft technologies. Part of the way they do this is by producing and distributing packages called 'application blocks.' An application block consists of a functional subsystem or software framework that can be valuable in several ways. Application blocks can be implemented in many types of applications as time-saving subsystems. They are also reference examples of software designed and developed using the best practices of Microsoft architecture. Application blocks are freely distributed with all source code and documentation.

The new version of Windows Forms in .NET 2.0 brings some exciting and much-needed enhancements that not only allow for more productivity, but also allow for creating some extremely professional looking applications that have the look and feel of many of the office applications we use every day. The goal of this article is to introduce many of the new features starting at the base level and building up, much as you would create an application, detailing each feature and how the features can help you.

This article describes a pattern that allows any Web site or Web application to launch and interact with .NET 2.0 Windows Forms applications that are deployed using Microsoft's new 'ClickOnce' technology. This is done by taking advantage of a feature that allows Windows Forms applications that are deployed using ClickOnce to receive querystring parameters.

The composite UI Application Block (called 'CAB' in the online community) is a new application block that is being developed by Microsoft patterns & practices and is scheduled for release shortly after the final release of .NET 2.0. The current code for the Composite UI Application Block is the first Community Technology Preview. As with any beta release, there could always be changes before the final version. The core design and concepts, however, are less likely to undergo any major changes, and it is worth taking a look at the architecture and design of the block for several reasons:

Microsoft Windows provides a process called the System Event Notification Service. This service raises events relative to interactive logon, network, and power changes. Using this service an application can be notified when network connectivity changes, when available power decreases, or when a person logs on, locks his or screen, or his or her screensaver starts. This service notifies COM+ of these events, which appropriates them to any subscribing application.

A speaking engagement at Tech-Ed 2003 in India prompted me to put my thoughts on paper for this article illustrating some common tips and tricks to accomplish often-requested Windows Forms controls feature requests. These tips and tricks are based on discussions in various newsgroups online as well as Microsoft presentations.