Accessing the appSettings Section

The .NET Framework provides a predefined configuration section called appSettings. The following example shows the declaration of the appSettings section as it appears in the machine configuration file (Machine.config).

<configuration>
      <!-- Configuration section declarations. -->
   <configSections>
     <!-- You do not need to declare the appSettings section. Machine.config ships with a declaration for this section. -->
      <section name="appSettings" 
               type="System.Web.Configuration.NameValueSectionHandler"/>
   </configSections>
</configuration>

The following example shows how to use an application setting in a configuration file using the built-in appSettings section**.**

<configuration>
  <!-- The following code uses the predefined appSettings section. -->
    <appSettings>
        <add key="Application Name" value="MyApplication" />
    </appSettings>
</configuration>

ConfigurationSettings.AppSettings is a special property that provides a shortcut to application settings defined in the <appSettings> section of the configuration file. The following example shows how to retrieve the application name defined in the previous configuration file example.

    Public Sub ReadMyAppSettings()
        Dim appName As String

        appName = ConfigurationSettings.AppSettings("Application Name")

        Console.WriteLine()
        Console.WriteLine("Reading AppSettings")
        Console.WriteLine("Application Name: " & appName)
    End Sub
[C#]
public void ReadMyAppSettings()
{
    string appName = ConfigurationSettings.AppSettings["Application Name"];

    Console.WriteLine();
    Console.WriteLine("Reading AppSettings");
    Console.WriteLine("Application Name: " + appName);
}

See Also

Configuration Section Settings | Configuration Sections Schema