对于这种情况，您有两种选择。您可以*在参数中使用通配符 ( ) {app}，表示“URI 的其余部分”；或者你可以给{app}部件一个默认值，如果它不存在，它将被使用。
您可以在http://msdn.microsoft.com/en-us/library/bb675245.aspx上查看有关 URI 模板的更多信息，下面的代码显示了这两种选择。
public class StackOverflow_15289120
{
[ServiceContract]
public class Service
{
[WebGet(UriTemplate = "RetrieveUserInformation/{hash}/{*app}")]
public string RetrieveUserInformation(string hash, string app)
{
return hash + " - " + app;
}
[WebGet(UriTemplate = "RetrieveUserInformation2/{hash}/{app=default}")]
public string RetrieveUserInformation2(string hash, string app)
{
return hash + " - " + app;
}
}
public static void Test()
{
string baseAddress = "http://" + Environment.MachineName + ":8000/Service";
WebServiceHost host = new WebServiceHost(typeof(Service), new Uri(baseAddress));
host.Open();
Console.WriteLine("Host opened");
WebClient c = new WebClient();
Console.WriteLine(c.DownloadString(baseAddress + "/RetrieveUserInformation/dsakldasda/Apple"));
Console.WriteLine();
c = new WebClient();
Console.WriteLine(c.DownloadString(baseAddress + "/RetrieveUserInformation/dsakldasda"));
Console.WriteLine();
c = new WebClient();
Console.WriteLine(c.DownloadString(baseAddress + "/RetrieveUserInformation2/dsakldasda"));
Console.WriteLine();
Console.Write("Press ENTER to close the host");
Console.ReadLine();
host.Close();
}
}