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DefaultAuthenticationEventArgs(HttpContext) Constructor

  • Reference

Definition

Namespace:
System.Web.Security
Assembly:
System.Web.dll

Initializes a new instance of the DefaultAuthenticationEventArgs class.

public:
 DefaultAuthenticationEventArgs(System::Web::HttpContext ^ context);
public DefaultAuthenticationEventArgs (System.Web.HttpContext context);
new System.Web.Security.DefaultAuthenticationEventArgs : System.Web.HttpContext -> System.Web.Security.DefaultAuthenticationEventArgs
Public Sub New (context As HttpContext)

Parameters

context
HttpContext

The context for the event.

Examples

The following code example uses the DefaultAuthentication_OnAuthenticate event to test whether the User property of the current HttpContext is null. If the property is null, the example sets the User property of the current HttpContext to a GenericPrincipal object where the Identity property of the GenericPrincipal object is a GenericIdentity object with a Name property value of "default".

Note

The DefaultAuthentication_OnAuthenticate event is raised before the AuthorizeRequest event. As a result, if you set the User property of the current HttpContext to a custom identity, it can affect the behavior of your application. For example, if you are using the FormsAuthentication class and you are ensuring that only authenticated users have access to your site, by using the authorization section and specifying <deny users="?" />, you will cause the deny element in this example to be ignored, as the user will have a name, which is "default". Instead you would specify <deny users="default" /> to ensure that only authenticated users can access your site.

public void DefaultAuthentication_OnAuthenticate(object sender,
                                                 DefaultAuthenticationEventArgs args)
{
  if (args.Context.User == null)
    args.Context.User = 
      new System.Security.Principal.GenericPrincipal(
        new System.Security.Principal.GenericIdentity("default"),
        new String[0]);
}

Public Sub DefaultAuthentication_OnAuthenticate(sender As Object, _
                                                args As DefaultAuthenticationEventArgs)
  If args.Context.User Is Nothing Then
    args.Context.User = _
      new System.Security.Principal.GenericPrincipal( _
        new System.Security.Principal.GenericIdentity("default"), _
        new String(0) {})
  End If
End Sub

Remarks

The DefaultAuthenticationModule object constructs a DefaultAuthenticationEventArgs object using the current HttpContext and passes it to the DefaultAuthentication_OnAuthenticate event.

You can use the Context property of the DefaultAuthenticationEventArgs object supplied to the DefaultAuthentication_OnAuthenticate event to set the User property of the current HttpContext to a custom IPrincipal object. If you do not specify a value for the User property of the HttpContext referenced by the Context property, the DefaultAuthenticationModule sets the User property of the HttpContext to a GenericPrincipal object that contains no user information.

The DefaultAuthentication_OnAuthenticate event is raised after the AuthenticateRequest event and before the AuthorizeRequest event. If you have an authorization section that depends on the user name to deny or allow access to your application, modifying the User property of the current HttpContext can affect the behavior of your application. Be sure that the user name you set during the DefaultAuthentication_OnAuthenticate event is considered when you specify the authorization section in your configuration.

Applies to

See also