Retrieving Configuration

ASP.NET allows developers to access configuration settings from within an application either by exposing configuration settings directly (as strongly typed properties) or by using general configuration APIs. The following sample shows a page that accesses the <browserCaps> configuration section using the Browser property of the System.Web.HttpRequest class. This is a hash table of attributes that reflect the capabilities of the browser client that is currently accessing the page. The actual <browserCaps> section data is included in the machine.config file.

VB BrowsCaps.aspx [Run Sample] | [View Source]

In addition to accessing configuration settings, as demonstrated above, developers also can use the System.Configuration.ConfigurationSettings class to retrieve the data for any arbitrary configuration section. Note that the particular object returned by ConfigurationSettings depends on the section handler mapped to the configuration section (see IConfigurationSectionHandler.Create). The following code demonstrates how you can access the configuration data exposed for a <customconfig> section. In this example, it is assumed that the configuration section handler returns an object of type CustomConfigSettings with the property Enabled.

Dim config As CustomConfigSettings = CType(ConfigurationSettings("customconfig"), CustomConfigSettings)

If config.Enabled = True Then
    ' Do something here.
End If

Using Application Settings

<configuration>
  <appSettings>
    <add key="pubs" value="server=(local)\NetSDK;database=pubs;Trusted_Connection=yes" />
    <add key="northwind" value="server=(local)\NetSDK;database=northwind;Trusted_Connection=yes" />
  </appSettings>
</configuration>

Dim dsn As String = ConfigurationSettings.AppSettings("pubs")

The following sample illustrates this technique.

VB Config1.aspx [Run Sample] | [View Source]