HttpClientHandler.ServerCertificateCustomValidationCallback Eigenschaft

Definition

Dient zum Abrufen oder Festlegen einer Rückrufmethode zum Überprüfen des Serverzertifikats.

public:
 property Func<System::Net::Http::HttpRequestMessage ^, System::Security::Cryptography::X509Certificates::X509Certificate2 ^, System::Security::Cryptography::X509Certificates::X509Chain ^, System::Net::Security::SslPolicyErrors, bool> ^ ServerCertificateCustomValidationCallback { Func<System::Net::Http::HttpRequestMessage ^, System::Security::Cryptography::X509Certificates::X509Certificate2 ^, System::Security::Cryptography::X509Certificates::X509Chain ^, System::Net::Security::SslPolicyErrors, bool> ^ get(); void set(Func<System::Net::Http::HttpRequestMessage ^, System::Security::Cryptography::X509Certificates::X509Certificate2 ^, System::Security::Cryptography::X509Certificates::X509Chain ^, System::Net::Security::SslPolicyErrors, bool> ^ value); };
public Func<System.Net.Http.HttpRequestMessage,System.Security.Cryptography.X509Certificates.X509Certificate2,System.Security.Cryptography.X509Certificates.X509Chain,System.Net.Security.SslPolicyErrors,bool> ServerCertificateCustomValidationCallback { get; set; }
member this.ServerCertificateCustomValidationCallback : Func<System.Net.Http.HttpRequestMessage, System.Security.Cryptography.X509Certificates.X509Certificate2, System.Security.Cryptography.X509Certificates.X509Chain, System.Net.Security.SslPolicyErrors, bool> with get, set
Public Property ServerCertificateCustomValidationCallback As Func(Of HttpRequestMessage, X509Certificate2, X509Chain, SslPolicyErrors, Boolean)

Eigenschaftswert

Eine Rückrufmethode zum Überprüfen des Serverzertifikats.

Beispiele

Im folgenden Codebeispiel wird das Serverzertifikat angezeigt.

static async Task Main()
{
    // Create an HttpClientHandler object and set to use default credentials
    HttpClientHandler handler = new HttpClientHandler();

    // Set custom server validation callback
    handler.ServerCertificateCustomValidationCallback = ServerCertificateCustomValidation;

    // Create an HttpClient object
    HttpClient client = new HttpClient(handler);

    // Call asynchronous network methods in a try/catch block to handle exceptions
    try
    {
        HttpResponseMessage response = await client.GetAsync("https://learn.microsoft.com/");

        response.EnsureSuccessStatusCode();

        string responseBody = await response.Content.ReadAsStringAsync();
        Console.WriteLine($"Read {responseBody.Length} characters");
    }
    catch (HttpRequestException e)
    {
        Console.WriteLine("\nException Caught!");
        Console.WriteLine($"Message: {e.Message} ");
    }

    // Need to call dispose on the HttpClient and HttpClientHandler objects
    // when done using them, so the app doesn't leak resources
    handler.Dispose();
    client.Dispose();
}

private static bool ServerCertificateCustomValidation(HttpRequestMessage requestMessage, X509Certificate2? certificate, X509Chain? chain, SslPolicyErrors sslErrors)
{
    // It is possible to inspect the certificate provided by the server.
    Console.WriteLine($"Requested URI: {requestMessage.RequestUri}");
    Console.WriteLine($"Effective date: {certificate?.GetEffectiveDateString()}");
    Console.WriteLine($"Exp date: {certificate?.GetExpirationDateString()}");
    Console.WriteLine($"Issuer: {certificate?.Issuer}");
    Console.WriteLine($"Subject: {certificate?.Subject}");

    // Based on the custom logic it is possible to decide whether the client considers certificate valid or not
    Console.WriteLine($"Errors: {sslErrors}");
    return sslErrors == SslPolicyErrors.None;
}

Hinweise

Dies ServerCertificateCustomValidationCallback kann verwendet werden, um das Serverzertifikat abzurufen und zu überprüfen.

Gilt für: