我已经创建了一个通用应用程序，它连接到Intranet上的WCF Web服务，它工作得很好，因为服务主机的地址是已知的。
由于性能和安全性（冗余）原因，系统的体系结构允许在不同主机中运行多个Web服务。所以我试图让我的应用程序发现每个服务，使用给定的合同，这是在同一个局域网上运行，但我无法做到这一点。
我正在尝试使用与非常相似的win32应用程序相同的方法：
var discoveryClient = new DiscoveryClient(new UdpDiscoveryEndpoint());
var findCriteria = new FindCriteria(typeof(INewProdColetorWCFService));
findCriteria.Duration = TimeSpan.FromSeconds(5);
var findResponse = await discoveryClient.FindTaskAsync(findCriteria);
Visual Studio“自动”为我添加所需的引用（System.ServiceModel.Discovery）as seen here
在设计时似乎没问题，但是当我尝试编译时，会出现错误：
在模块System.ServiceModel.dll中找不到类型System.ServiceModel.Configuration.ServiceModelConfigurationElementCollection`1。
你们有没有在UWP中做到这一点？你能帮助我吗？ 提前谢谢，iuri。
ps：我也发布了this question in MSDN
答案 0 :(得分：0)
UWP目前不支持WS-Discovery API。详情请见https://msdn.microsoft.com/en-us/library/windows/apps/mt185502.aspx。 文档中没有针对UWP应用程序的System.ServiceModel.Discovery API支持。但是你可以在win32应用程序中使用它。 如果您需要此功能，可以将您的想法提交到UserVoice网站：https://wpdev.uservoice.com/forums/110705-universal-windows-platform
答案 1 :(得分：0)
我不知道我是否应该回答我自己的问题，但我认为对于任何想要做同样事情的人来说这可能是有用的，所以就在这里。
由于WS-Discovery API在UWP中不可用，我必须以另一种方式进行。使用套接字是我能找到的最佳选择。所以每个WS都会监听一个特定的端口，等待一些广播的消息搜索在局域网中运行的WS。
WS实现是win32，这是所需的代码：
private byte[] dataStream = new byte[1024];
private Socket serverSocket;
private void InitializeSocketServer(string id)
{
// Sets the server ID
this._id = id;
// Initialise the socket
serverSocket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
// Initialise the IPEndPoint for the server and listen on port 30000
IPEndPoint server = new IPEndPoint(IPAddress.Any, 30000);
// Associate the socket with this IP address and port
serverSocket.Bind(server);
// Initialise the IPEndPoint for the clients
IPEndPoint clients = new IPEndPoint(IPAddress.Any, 0);
// Initialise the EndPoint for the clients
EndPoint epSender = (EndPoint)clients;
// Start listening for incoming data
serverSocket.BeginReceiveFrom(this.dataStream, 0, this.dataStream.Length, SocketFlags.None, ref epSender, new AsyncCallback(ReceiveData), epSender);
}
private void ReceiveData(IAsyncResult asyncResult)
{
// Initialise the IPEndPoint for the clients
IPEndPoint clients = new IPEndPoint(IPAddress.Any, 0);
// Initialise the EndPoint for the clients
EndPoint epSender = (EndPoint)clients;
// Receive all data. Sets epSender to the address of the caller
serverSocket.EndReceiveFrom(asyncResult, ref epSender);
// Get the message received
string message = Encoding.UTF8.GetString(dataStream);
// Check if it is a search ws message
if (message.StartsWith("SEARCHWS", StringComparison.CurrentCultureIgnoreCase))
{
// Create a response messagem indicating the server ID and it's URL
byte[] data = Encoding.UTF8.GetBytes($"WSRESPONSE;{this._id};http://{GetIPAddress()}:5055/wsserver");
// Send the response message to the client who was searching
serverSocket.BeginSendTo(data, 0, data.Length, SocketFlags.None, epSender, new AsyncCallback(this.SendData), epSender);
}
// Listen for more connections again...
serverSocket.BeginReceiveFrom(this.dataStream, 0, this.dataStream.Length, SocketFlags.None, ref epSender, new AsyncCallback(this.ReceiveData), epSender);
}
private void SendData(IAsyncResult asyncResult)
{
serverSocket.EndSend(asyncResult);
}
客户端实现是UWP。我创建了以下类来进行搜索：
public class WSDiscoveryClient
{
public class WSEndpoint
{
public string ID;
public string URL;
}
private List<WSEndpoint> _endPoints;
private int port = 30000;
private int timeOut = 5; // seconds
/// <summary>
/// Get available Webservices
/// </summary>
public async Task<List<WSEndpoint>> GetAvailableWSEndpoints()
{
_endPoints = new List<WSEndpoint>();
using (var socket = new DatagramSocket())
{
// Set the callback for servers' responses
socket.MessageReceived += SocketOnMessageReceived;
// Start listening for servers' responses
await socket.BindServiceNameAsync(port.ToString());
// Send a search message
await SendMessage(socket);
// Waits the timeout in order to receive all the servers' responses
await Task.Delay(TimeSpan.FromSeconds(timeOut));
}
return _endPoints;
}
/// <summary>
/// Sends a broadcast message searching for available Webservices
/// </summary>
private async Task SendMessage(DatagramSocket socket)
{
using (var stream = await socket.GetOutputStreamAsync(new HostName("255.255.255.255"), port.ToString()))
{
using (var writer = new DataWriter(stream))
{
var data = Encoding.UTF8.GetBytes("SEARCHWS");
writer.WriteBytes(data);
await writer.StoreAsync();
}
}
}
private async void SocketOnMessageReceived(DatagramSocket sender, DatagramSocketMessageReceivedEventArgs args)
{
// Creates a reader for the incoming message
var resultStream = args.GetDataStream().AsStreamForRead(1024);
using (var reader = new StreamReader(resultStream))
{
// Get the message received
string message = await reader.ReadToEndAsync();
// Cheks if the message is a response from a server
if (message.StartsWith("WSRESPONSE", StringComparison.CurrentCultureIgnoreCase))
{
// Spected format: WSRESPONSE;<ID>;<HTTP ADDRESS>
var splitedMessage = message.Split(';');
if (splitedMessage.Length == 3)
{
var id = splitedMessage[1];
var url = splitedMessage[2];
_endPoints.Add(new WSEndpoint() { ID = id, URL = url });
}
}
}
}
}
如果您发现错误，请随时发表评论，请告诉我它是否对您有所帮助。
答案 2 :(得分：0)
我自己做了一些研究时遇到过这个问题。在阅读https://en.wikipedia.org/wiki/WS-Discovery并使用Wireshark解读一些细节后，我得到了一个支持Microsoft的WS-Discovery规范的基本概念证明，这意味着服务器端不需要进行任何更改。
我现在已经离开了这个项目，但希望有人可以从中获得一些用处：
public class WSDiscoveryResponse
{
private readonly string
_content,
_remotePort;
private readonly HostName
_remoteAddress;
public WSDiscoveryResponse(string content, HostName remoteAddress, string remotePort)
{
this._content = content;
this._remoteAddress = remoteAddress;
this._remotePort = remotePort;
}
}
public class WSDiscoveryClient
{
private const string
SRC_PORT = "0",//represents 'use any port available'
DEST_IP_WSDISCOVERY = "239.255.255.250", //broadcast (ish)
DEST_PORT_WSDISCOVERY = "3702";
private TimeSpan _timeout = TimeSpan.FromSeconds(5);
private List<WSDiscoveryResponse> _wsresponses = null;
/// <summary>
/// Get available Webservices
/// </summary>
public async Task<List<WSDiscoveryResponse>> GetAvailableWSEndpoints()
{
_wsresponses = new List<WSDiscoveryResponse>();
using (var socket = new DatagramSocket())
{
try
{
socket.MessageReceived += SocketOnMessageReceived;
//listen for responses to future message
await socket.BindServiceNameAsync(SRC_PORT);
//broadcast interrogation
await SendDiscoveryMessage(socket);
//wait for broadcast responses
await Task.Delay(_timeout).ConfigureAwait(false);
}
catch (Exception ex)
{
SocketErrorStatus webErrorStatus = SocketError.GetStatus(ex.GetBaseException().HResult);
}
}
return _wsresponses;
}
private string BuildDiscoveryMessage()
{
const string outgoingMessageFormat = @"<s:Envelope xmlns:s=""http://www.w3.org/2003/05/soap-envelope"" xmlns:a=""http://www.w3.org/2005/08/addressing""><s:Header><a:Action s:mustUnderstand=""1"">http://docs.oasis-open.org/ws-dd/ns/discovery/2009/01/Probe</a:Action><a:MessageID>urn:uuid:{0}</a:MessageID><a:ReplyTo><a:Address>http://www.w3.org/2005/08/addressing/anonymous</a:Address></a:ReplyTo><a:To s:mustUnderstand=""1"">urn:docs-oasis-open-org:ws-dd:ns:discovery:2009:01</a:To></s:Header><s:Body><Probe xmlns=""http://docs.oasis-open.org/ws-dd/ns/discovery/2009/01""><d:Types xmlns:d=""http://docs.oasis-open.org/ws-dd/ns/discovery/2009/01"" xmlns:dp0=""http://tempuri.org/"">dp0:IDiscoveryService</d:Types><Duration xmlns=""http://schemas.microsoft.com/ws/2008/06/discovery"">PT5S</Duration></Probe></s:Body></s:Envelope>";
string outgoingMessage = string.Format(outgoingMessageFormat, Guid.NewGuid().ToString());
return outgoingMessage;
}
private async Task SendDiscoveryMessage(DatagramSocket socket)
{
using (var stream = await socket.GetOutputStreamAsync(new HostName(DEST_IP_WSDISCOVERY), DEST_PORT_WSDISCOVERY))
{
string message = BuildDiscoveryMessage();
var data = Encoding.UTF8.GetBytes(message);
using (var writer = new DataWriter(stream))
{
writer.WriteBytes(data);
await writer.StoreAsync();
}
}
}
private void SocketOnMessageReceived(DatagramSocket sender, DatagramSocketMessageReceivedEventArgs args)
{
var dr = args.GetDataReader();
string message = dr.ReadString(dr.UnconsumedBufferLength);
_wsresponses.Add(new WSDiscoveryResponse(message, args.RemoteAddress, args.RemotePort));
}
}