(Editor's Note: Information in this buyer's guide comes from vendor representatives and resources and is meant to jump-start, not replace, your own research; also, some products might have been left out, either as an oversight or from lack of vendor response.)
The Microsoft .NET framework has been around for years—the company first announced it back in 2000. It makes the process of creating applications smoother for SQL Server developers—and just about any other kind of developer. Because .NET was designed from the ground up to make different programming languages and Microsoft products get along, it's an important product for SQL developers. If there's something you need .NET to do, but the functions you're looking for just aren't around, you can take advantage of .NET's ability to bring different products together.
Innovations in the recent versions of Visual Studio have made it easier to access your databases from within applications, but there's always some other function that a developer could wish for. That's where .NET components come in. The products listed in this month's buyer's guide table are just a sample of what's available. Because .NET has so many uses, some products listed may be only peripherally related to SQL Server. On the same note, some vendors chose not to participate in the buyer's guide because they didn't feel SQL Server was a primary use of their products, but SQL Server developers could still find them useful. Always do your own research, and if you don't see a product to do what you need on the list, keep looking.
Even the relatively small list here includes products that do very different things. Some of the products use visual UI controls, others don't. One component helps you create Windows forms. Another assists in making visualizations, such as charts and graphs. A third targets creation of schedules. The bottom line is that there's a huge variety of .NET component products out there, so if you need something and you can't find it, you're probably not looking hard enough.
Now that .NET 4.0 and Visual Studio (VS) 2010 are available, you have one more factor to consider when you're looking at .NET components. VS 2010 brings many new features to the table over VS 2008, such as refined LINQ-to-SQL, an improved code-writing environment (with better multimonitor support), and database-specific functions. See Visual Studio 2010 for Database Professionals for more on what's new in VS 2010 and .NET 4.0.
Many of the products in the buyer's guide table don't support .NET 4.0. It's possible to use VS2010 to create applications for older .NET platforms, but be careful. If you're on the cutting edge and you want to take advantage of Microsoft's latest developer offerings, you'll have to deal with your component options being cut. Vendors are usually pretty quick to upgrade their products to be compatible with Microsoft's latest versions, but check with a specific vendor before committing to them.
In addition to making sure you get component products that work with your version of VS and the .NET framework, make sure to look at what other technologies the components work with. In many areas of modern computing, you can the list of supported technologies to look pretty much the same for all products of a certain time. That's not the case here—support for ASP.NET, AJAX, and mobile controls varies greatly from one product to another.
If you're interested in learning more about developing with .NET, I recommend checking out our sister publication, DevProConnections. This publication, formerly known as asp.netPRO, has a large archive of articles on the .NET environment, VS, and databases.