SocketsHttpHandler.ConnectCallback Egenskap

Definition

Hämtar eller anger ett anpassat återanrop som används för att öppna nya anslutningar.

public:
 property Func<System::Net::Http::SocketsHttpConnectionContext ^, System::Threading::CancellationToken, System::Threading::Tasks::ValueTask<System::IO::Stream ^>> ^ ConnectCallback { Func<System::Net::Http::SocketsHttpConnectionContext ^, System::Threading::CancellationToken, System::Threading::Tasks::ValueTask<System::IO::Stream ^>> ^ get(); void set(Func<System::Net::Http::SocketsHttpConnectionContext ^, System::Threading::CancellationToken, System::Threading::Tasks::ValueTask<System::IO::Stream ^>> ^ value); };
public Func<System.Net.Http.SocketsHttpConnectionContext,System.Threading.CancellationToken,System.Threading.Tasks.ValueTask<System.IO.Stream>>? ConnectCallback { get; set; }
member this.ConnectCallback : Func<System.Net.Http.SocketsHttpConnectionContext, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<System.IO.Stream>> with get, set
Public Property ConnectCallback As Func(Of SocketsHttpConnectionContext, CancellationToken, ValueTask(Of Stream))

Egenskapsvärde

En motringningsmetod för att skapa en dataström.

Undantag

En åtgärd har redan startats på den aktuella instansen.

Den aktuella instansen har tagits bort.

Exempel

I följande kodexempel anges TCP KeepAlive på den underliggande Socket.

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

    handler.ConnectCallback = async (ctx, ct) =>
    {
        DnsEndPoint dnsEndPoint = ctx.DnsEndPoint;
        IPAddress[] addresses = await Dns.GetHostAddressesAsync(dnsEndPoint.Host, dnsEndPoint.AddressFamily, 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(addresses, dnsEndPoint.Port, 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://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} ");
    }
}

Gäller för