uwp httplistener不听

Question

我有一个ToggleSwitch，当它打开时会启动一个HttpListener。下面是打开侦听器的代码。

我的问题是HttpListener没有在监听。我通过邮递员请求http://localhost:8023，请求总是超时。只有在调用GetContextCallBack时才调用httpListener.Stop()。我的代码有什么问题？它在控制台应用程序中工作，但在UWP中不工作。

private void LaunchLocalServer(int port)
{
    httpListener = new HttpListener();
    httpListener.Prefixes.Add($"http://127.0.0.1:{port}/");
    httpListener.Start();
    httpListener.BeginGetContext(new AsyncCallback(GetContextCallBack), httpListener);
}

private void GetContextCallBack(IAsyncResult ar)
{
    try
    {
        HttpListener _listener = ar.AsyncState as HttpListener;
        if (_listener.IsListening)
        {
            return;
        }

        HttpListenerContext context = _listener.EndGetContext(ar);
        _listener.BeginGetContext(new AsyncCallback(GetContextCallBack), _listener);

        HttpListenerResponse response = context.Response;
        response.StatusCode = (int)HttpStatusCode.OK;
        response.ContentType = "application/json;charset=UTF-8";
        response.ContentEncoding = Encoding.UTF8;
        response.AppendHeader("Content-Type", "application/json;charset=UTF-8");

        var abcOject = new
        {
            code = "200",
            description = "success",
            data = "time=" + DateTime.Now
        };
        string responseString = JsonConvert.SerializeObject(abcOject,
            new JsonSerializerSettings()
            {
                StringEscapeHandling = StringEscapeHandling.EscapeNonAscii
            });

        using (StreamWriter writer = new StreamWriter(response.OutputStream, Encoding.UTF8))
        {
            writer.Write(responseString);
            writer.Close();
            response.Close();
        }
    }
    catch (Exception ex)
    {
        Log.Warn($"handle response failed {ex}");
    }
}

完整代码是这里。

Answer 1

这种行为的一个普遍原因是，您需要首先启用UWP应用程序的本地回送( UWP启用本地网络回送 )。UWP应用程序在沙箱中运行，并与系统资源隔离。启用本地网络回送可以使UWP应用程序能够访问本地网络资源。