1、在此，借用一下WCF，创建控制台程序，构建解决方案如图，由于只是简单演示，具体细节先不做深究：

IDomain.cs、DomainService.cs、clentaccesspolicy.xml是为了实现跨域，Site是数据库里的基站信息model，ISiteService和SiteService为模拟的地图查询服务，具体代码为：

IDomain.cs

  [ServiceContract]public interface IDomain{[OperationContract][WebGet(UriTemplate = "ClientAccessPolicy.xml")]Message ProvidePolicyFile();}

  [ServiceContract]public interface ISiteService{[OperationContract]List<Site> GetSites();}

Site.cs

  [DataContract]public class Site{[DataMember]public string GID { get; set; }[DataMember]public string SiteName { get; set; }[DataMember]public string Geom { get; set; }}

DomainService.cs

  public class DomainService : IDomain{public System.ServiceModel.Channels.Message ProvidePolicyFile(){MemoryStream ms = new MemoryStream();using (FileStream fs = File.OpenRead(@"clientaccesspolicy.xml")){int length = (int)fs.Length;byte[] data = new byte[length];fs.Position = 0;fs.Read(data, 0, length);ms = new MemoryStream(data);}XmlReader reader = XmlReader.Create(ms);Message result = Message.CreateMessage(MessageVersion.None, "", reader);return result;}}

SiteService.cs

 public class SiteService:ISiteService{private DataSet ds = new DataSet();private DataTable dt = new DataTable();public List<Site> GetSites(){List<Site> source = new List<Site>();try{// PostgeSQL-style connection string        string connstring = String.Format("Server={0};Port={1};User Id={2};Password={3};Database={4};", "localhost", "5432", "postgres", "sa", "postgis20");// Making connection with Npgsql provider           NpgsqlConnection conn = new NpgsqlConnection(connstring);conn.Open();// quite complex sql statement                  // data adapter making request from our connection//string sql = "SELECT * from cellcover_region";string sql = "SELECT a.* FROM public.cellcover_region as a, site_font_point as b where b.gid=1 and ST_Within(b.geom,a.geom)";NpgsqlDataAdapter da = new NpgsqlDataAdapter(sql, conn);          ds.Reset();// filling DataSet with result from NpgsqlDataAdapter        da.Fill(ds);// since it C# DataSet can handle multiple tables, we will select first           dt = ds.Tables[0]; int count = dt.Rows.Count;for (int i = 0; i < count; i++){DataRow dr = dt.Rows[i];Site site = new Site{GID = dr[0].ToString(),SiteName = dr[1].ToString(),Geom = dr[2].ToString()};source.Add(site);}conn.Close();}catch (Exception ex){throw ex;}return source;}}

Program.cs

  static void Main(string[] args){ServiceHost host = new ServiceHost(typeof(SiteService));ServiceHost crossDomainserviceHost = new ServiceHost(typeof(DomainService));host.Opened += delegate{Console.WriteLine("服务已经启动，按任意键终止...");};crossDomainserviceHost.Opened += delegate{Console.WriteLine("跨域服务已经启动，按任意键终止...");};crossDomainserviceHost.Open();host.Open();Console.ReadKey();host.Close();host.Abort();crossDomainserviceHost.Close();crossDomainserviceHost.Abort();}

编译运行，效果如图，表示服务正常启动：

下面两点在后续节中再做详细补充：

2、把上节做的silverlight客户端，添加该WCF服务，在交互过程中（如点击图元）调用服务方法，完成数据展现

3、wpf做地图客户端，添加该WCF服务，在交互过程中调用服务，完成地图展现