async Task DiscoverUdp(IPAddress local, IPEndPoint ep)
{
XTrace.WriteLine("DiscoverUdp: {0} -> {1}", local, ep);
// 构建请求
var enc = new JsonEncoder();
var msg = enc.CreateRequest("Api/Info", null);
var req = msg.ToPacket().ReadBytes();
var udp = new UdpClient(ep.AddressFamily)
{
EnableBroadcast = true
};
if (local != null)
{
udp.Client.Bind(new IPEndPoint(local, Rand.Next(1000, 60000)));
}
// 发送
udp.Send(req, req.Length, ep);
// 多次接收
while (true)
{
try
{
var source = new CancellationTokenSource(3_000);
var rs = await udp.ReceiveAsync(source.Token);
if (rs.Buffer != null)
{
msg = new DefaultMessage();
msg.Read(rs.Buffer);
if (enc.Decode(msg, out var action, out var code, out var data) && code == 0)
{
// 解码结果
var result = enc.DecodeResult(action, data, msg);
XTrace.WriteLine("Receive[{0}] {1}", udp.Client.LocalEndPoint, result.ToJson());
var ai = enc.Convert(result, typeof(ApiItem)) as ApiItem;
if (ai != null)
{
Invoke(() => ShowItem(ai));
}
}
}
}
catch (OperationCanceledException)
{
break;
}
}
}