SocketsHttpHandler.ConnectCallback Propriedade

Definição

Namespace:

System.Net.Http

Assembly:

System.Net.Http.dll

Origem:

SocketsHttpHandler.cs

Obtém ou define um retorno de chamada personalizado usado para abrir novas conexões.

C#

public Func<System.Net.Http.SocketsHttpConnectionContext,System.Threading.CancellationToken,System.Threading.Tasks.ValueTask<System.IO.Stream>>? ConnectCallback { get; set; }

Valor da propriedade

Func<SocketsHttpConnectionContext,CancellationToken,ValueTask<Stream>>

Um método de retorno de chamada para criar um fluxo.

Exemplos

O exemplo de código a seguir define TCP KeepAlive no subjacente Socket.

C#

static async Task Main()
{
    using SocketsHttpHandler handler = new SocketsHttpHandler();

    handler.ConnectCallback = async (ctx, ct) =>
    {
        var s = new Socket(SocketType.Stream, ProtocolType.Tcp) { NoDelay = true };
        try
        {
            s.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.KeepAlive, true);
            s.SetSocketOption(SocketOptionLevel.Tcp, SocketOptionName.TcpKeepAliveTime, 5);
            s.SetSocketOption(SocketOptionLevel.Tcp, SocketOptionName.TcpKeepAliveInterval, 5);
            s.SetSocketOption(SocketOptionLevel.Tcp, SocketOptionName.TcpKeepAliveRetryCount, 5);
            await s.ConnectAsync(ctx.DnsEndPoint, ct);
            return new NetworkStream(s, ownsSocket: true);
        }
        catch
        {
            s.Dispose();
            throw;
        }
    };

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

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

Aplica-se a