Third-Party Controls

Visual Basic comes with a large number of useful controls ready to go, but there are many other controls you can use if you need them. If you right-click the Toolbox and select Choose Items, you can select from a huge list of .NET Framework and COM components available on your system.

You can also obtain other controls provided by other companies and available for purchase and sometimes for free on the Web. Many of these controls perform specialized tasks such as generating bar codes, making shaped forms, warping images, and providing special graphical effects.

Other controls extend the standard controls to provide more power or flexibility. Several controls are available that draw two- and three-dimensional charts and graphs. Other controls provide more powerful reporting services than those provided by Visual Studio’s own tools.

If you use any major web search engine to search for “windows forms controls,” you will find lots of web sites where you can download controls for free or for a price. A few places you might like to explore include:

• MVPs.org (www.mvps.org), a site leading to resources provided by people related to Microsoft’s Most Valuable Professional (MVP) program. The Common Controls Replacement Project (ccrp.mvps.org) provides controls that duplicate and enhance standard Visual Basic 6 controls. Development on this project has stopped but some of the old Visual Basic 6 controls may give you some ideas for building controls of your own. MVPs.org is also a good general resource.

• Windows Forms .NET (www.windowsforms.net), Microsoft’s official Windows Forms .NET community.

• ASP.NET (www.asp.net), Microsoft’s official ASP.NET community.

• Download.com (www.download.com)

• Shareware.com (www.shareware.com)

• Shareware Connection (www.sharewareconnection.com)

You should use these as a starting point for your own search, not as a definitive list. You can download controls from hundreds (if not thousands) of web sites.

Tip 

You should also show some restraint in downloading third-party controls and products in general. Every time you add another control to a project, you make the project depend on that control. If you later move the project to a newer version of Visual Basic, you must ensure that the control works with that version. Similarly, if the vendor makes a new version of the control, you must find out if it works with your version of Visual Basic. If it doesn’t, you may be stuck using an older, unsupported version of the control.

If controls and tools interact with each other, the problem becomes much more difficult. If anything changes, you must find a set of versions for all of the tools that can work correctly together.

I try to keep my use of third-party controls to a bare minimum because, when I write a book, I generally cannot assume that you have a particular third-party control. I use tools such as WinZip (www.WinZip.com) and Internet Download Manager (www.InternetDownloadManager.com) outside of projects, but nothing inside them.

Use a third-party control if it will save you a lot of work. But, before you do, ask yourself how much work would it be to do without the control and how much work it will be to replace it if you need to move to a new version of Visual Basic.