AuthenticationManager.PreAuthenticate(WebRequest, ICredentials) Method

Definition

Namespace:

System.Net

Assembly:

System.Net.Requests.dll

Source:

AuthenticationManager.cs

Caution

The AuthenticationManager Authenticate and PreAuthenticate methods are not supported and throw PlatformNotSupportedException.

Preauthenticates a request.

public:
 static System::Net::Authorization ^ PreAuthenticate(System::Net::WebRequest ^ request, System::Net::ICredentials ^ credentials);

[System.Obsolete("The AuthenticationManager Authenticate and PreAuthenticate methods are not supported and throw PlatformNotSupportedException.", DiagnosticId="SYSLIB0009", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
public static System.Net.Authorization? PreAuthenticate (System.Net.WebRequest request, System.Net.ICredentials credentials);

[<System.Obsolete("The AuthenticationManager Authenticate and PreAuthenticate methods are not supported and throw PlatformNotSupportedException.", DiagnosticId="SYSLIB0009", UrlFormat="https://aka.ms/dotnet-warnings/{0}")>]
static member PreAuthenticate : System.Net.WebRequest * System.Net.ICredentials -> System.Net.Authorization

Public Shared Function PreAuthenticate (request As WebRequest, credentials As ICredentials) As Authorization

Parameters

request

WebRequest

A request to an internet resource.

credentials

ICredentials

The credentials associated with the request.

Returns

Authorization

An instance of the Authorization class if the request can be preauthenticated; otherwise, null. If credentials is null, this method returns null.

Attributes

ObsoleteAttribute

Exceptions

PlatformNotSupportedException

.NET Core and .NET 5+ only: In all cases.

ArgumentNullException

request is null.

Remarks

If the authentication module can preauthenticate the request, the PreAuthenticate method returns an Authentication instance and sends the authorization information to the server preemptively instead of waiting for the resource to issue a challenge. This behavior is outlined in section 3.3 of RFC 2617 (HTTP Authentication: Basic and Digest Access Authentication). Authentication modules that support preauthentication allow clients to improve server efficiency by avoiding extra round trips caused by authentication challenges.

Authorization modules that can preauthenticate requests set the IAuthenticationModule.CanPreAuthenticate property to true.