ASP.NET in a Nutshell

Application File Types

A number of different file types are associated with an ASP.NET application, and it’s important to understand the purpose of each type, even if you aren’t using all of them in your current applications. In this section, we’ll look at the major file types associated with ASP.NET Web Applications and web services and what each of them does.

web.config

web.config is the file type used for configuration of various settings within an ASP.NET application. Applications may contain more than one web.config file (though there may be only one per directory or subdirectory), and the web.config files are applied in an hierarchical fashion. What this means is that if you have defined a particular setting (such as the user accounts permitted to access that directory) in the web.config file at the root of your application, this setting applies to the application and all of its subdirectories, if it has any. You can override that setting for a particular subdirectory by using a web.config file in a subdirectory of the application. The web.config files use an XML-based syntax, and both the tag names and their attributes are case-sensitive.

web.config provides configuration settings for:

• Application-specific settings, such as connection string information (since the web.config file resides within the web application’s file space, it is probably best to avoid storing sensitive information such as passwords in a configuration file).

• Authentication and authorization.

• Browser ...