相关疑难解决方法(0)

我以前使用过BeginAccept()和BeginRead(),但与Visual Studio 2012我想利用新的异步的(async,await)功能在我的socket服务器程序.

我该如何完成AcceptAsync和ReceiveAsync功能？

using System.Net;
using System.Net.Sockets;

namespace OfficialServer.Core.Server
{
    public abstract class CoreServer
    {
        private const int ListenLength = 500;
        private const int ReceiveTimeOut = 30000;
        private const int SendTimeOut = 30000;
        private readonly Socket _socket;

        protected CoreServer(int port, string ip = "0.0.0.0")
        {
            _socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            _socket.Bind(new IPEndPoint(IPAddress.Parse(ip), port));
            _socket.Listen(ListenLength);
            _socket.ReceiveTimeout = ReceiveTimeOut;
            _socket.SendTimeout = SendTimeOut;
            _socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.KeepAlive, true);
            _socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.DontLinger, true); …

我想有一个通用的可重用的代码为包装EAP模式的任务,类似什么东西Task.Factory.FromAsync了呢BeginXXX/EndXXXAPM模式.

例如:

private async void Form1_Load(object sender, EventArgs e)
{
    await TaskExt.FromEvent<EventArgs>(
        handler => this.webBrowser.DocumentCompleted += 
            new WebBrowserDocumentCompletedEventHandler(handler),
        () => this.webBrowser.Navigate("about:blank"),
        handler => this.webBrowser.DocumentCompleted -= 
            new WebBrowserDocumentCompletedEventHandler(handler),
        CancellationToken.None);

    this.webBrowser.Document.InvokeScript("setTimeout", 
        new[] { "document.body.style.backgroundColor = 'yellow'", "1" });
}

到目前为止,它看起来像这样:

public static class TaskExt
{
    public static async Task<TEventArgs> FromEvent<TEventArgs>(
        Action<EventHandler<TEventArgs>> registerEvent,
        Action action,
        Action<EventHandler<TEventArgs>> unregisterEvent,
        CancellationToken token)
    {
        var tcs = new TaskCompletionSource<TEventArgs>();

        EventHandler<TEventArgs> handler = (sender, args) =>
            tcs.TrySetResult(args);

        registerEvent(handler);
        try
        {
            using …

在使用异步套接字的 MSDN示例中，套接字中的接收数据是通过从 BeginReceive 调用的回调处理程序中重复调用异步 BeginReceive 来完成的：

private static void ReceiveCallback( IAsyncResult ar ) {
//...Skipped...
        if (bytesRead > 0) {
            // There might be more data, so store the data received so far.
            state.sb.Append(Encoding.ASCII.GetString(state.buffer,0,bytesRead));
                //  Get the rest of the data.
            client.BeginReceive(state.buffer,0,StateObject.BufferSize,0,
                new AsyncCallback(ReceiveCallback), state);
        } else {
// ...Skipped...
}

http://msdn.microsoft.com/en-us/library/bbx2eya8(v=vs.110).aspx

是否有必要从已经在单独线程中执行的处理程序再次进行异步调用？可以简单地在此处理程序中循环使用 Receive 吗？就像是：

while (bytesRead) {

bytesRead = client.Receive(state.buffer, 0, client.Available, 
                                   SocketFlags.None);
// Etc...
}