UdpClient.EndReceive(IAsyncResult, IPEndPoint) 方法

定义

结束挂起的异步接收。

public:
 cli::array <System::Byte> ^ EndReceive(IAsyncResult ^ asyncResult, System::Net::IPEndPoint ^ % remoteEP);
public byte[] EndReceive(IAsyncResult asyncResult, ref System.Net.IPEndPoint? remoteEP);
public byte[] EndReceive(IAsyncResult asyncResult, ref System.Net.IPEndPoint remoteEP);
member this.EndReceive : IAsyncResult * IPEndPoint -> byte[]
Public Function EndReceive (asyncResult As IAsyncResult, ByRef remoteEP As IPEndPoint) As Byte()

参数

asyncResult
IAsyncResult

调用 BeginReceive(AsyncCallback, Object) 后返回的 IAsyncResult 对象。

remoteEP
IPEndPoint

指定的远程终结点。

返回

Byte[]

如果成功,则返回包含数据报数据的字节数组。

例外

asyncResultnull

BeginReceive(AsyncCallback, Object) 方法的调用未返回 asyncResult

尝试访问基础 Socket 时出错。

已关闭基础 Socket

示例

下面的代码示例使用 BeginSend 完成服务器响应的异步接收。

public struct UdpState
{
    public UdpClient u;
    public IPEndPoint e;
}

public static bool messageReceived = false;

public static void ReceiveCallback(IAsyncResult ar)
{
    UdpClient u = ((UdpState)(ar.AsyncState)).u;
    IPEndPoint e = ((UdpState)(ar.AsyncState)).e;

    byte[] receiveBytes = u.EndReceive(ar, ref e);
    string receiveString = Encoding.ASCII.GetString(receiveBytes);

    Console.WriteLine($"Received: {receiveString}");
    messageReceived = true;
}

public static void ReceiveMessages()
{
    // Receive a message and write it to the console.
    IPEndPoint e = new IPEndPoint(IPAddress.Any, s_listenPort);
    UdpClient u = new UdpClient(e);

    UdpState s = new UdpState();
    s.e = e;
    s.u = u;

    Console.WriteLine("listening for messages");
    u.BeginReceive(new AsyncCallback(ReceiveCallback), s);

    // Do some work while we wait for a message. For this example, we'll just sleep
    while (!messageReceived)
    {
        Thread.Sleep(100);
    }
}

注解

此方法将阻止,直到操作完成。

若要同步执行此操作,请使用 Receive 方法。

适用于