Visual Basic 2005: A Developer's Notebook

Use Strongly Typed Configuration Settings

Applications commonly need configuration settings to nail down details like file locations, database connection strings, and user preferences. Rather than hardcoding these settings (or inventing your own mechanism to store them), .NET lets you add them to an application-specific configuration file. This allows you to adjust values on a whim by editing a text file without recompiling your application.

Note

Use error-proof configuration settings by the application designer.

In Visual Studio 2005, configuration settings are even easier to use. That's because they're automatically compiled into a custom class that provides strongly typed access to them. That means you can retrieve settings using properties, with the help of IntelliSense, instead of relying on string-based lookups. Even better, .NET enhances this model with the ability to use updatable, user-specific settings to track preferences and other information. You'll see both of these techniques at work in this lab.

How do I do that?

Every custom configuration setting is defined with a unique string name. In previous versions of .NET, you could retrieve the value of a configuration setting by looking up the value by its string name in a collection. However, if you use the wrong name, you wouldn't realize your error until you run the code and it fails with a runtime exception.

In Visual Studio 2005, the story is much improved. To add a new configuration setting, double-click the My Project ...