多源在线与离线数据读取三（天地图切片读法）

public class NGCCTiledMapLayer : TiledMapServiceLayer

    {

        //****************根据天地图的实际地址修改   {baseUrl}   参数*************//

       // privateconst string baseUrl ="http://map.sxch.gov.cn:7001/ge ... 3B%3B

        privateconst stringbaseUrl1 = "http://tile";

       // privateconst string baseUrl2 = ".tianditu.com/DataServer?T=A0512_EMap&";

        privateconst stringbaseUrl2 = ".tianditu.com/DataServer?T=B0627_EMap1112&";

        System.Randomra = new System.Random();

        privateconst int WKID= 4326;

 

         public override voidInitialize()

         {

             //图层的全图范围

             this.FullExtent= new ESRI.ArcGIS.Client.Geometry.Envelope(-180,-90,180,90)

             {

                  SpatialReference = new ESRI.ArcGIS.Client.Geometry.SpatialReference(WKID)

             };          

            //图层的空间参考

             this.SpatialReference= new ESRI.ArcGIS.Client.Geometry.SpatialReference(WKID);

            

            //设置切片的信息. 每个切片的大小256x256px, 14级

             this.TileInfo= new TileInfo()

             {

                  Height = 256,

                  Width = 256,

                  Origin = new ESRI.ArcGIS.Client.Geometry.MapPoint(-180, 90) { SpatialReference = new ESRI.ArcGIS.Client.Geometry.SpatialReference(WKID) },

                  Lods = new ESRI.ArcGIS.Client.Lod[20]

             };

            

            //设置每一级别的分辨率.每一级别的分辨率都是前一个级别的一半

            doubleresolution = 0.70391441567318025 * 1.99775;   //**************** 根据天地图的实际地址修改 调节系数    *************//

            for(int i = 0; i < TileInfo.Lods.Length; i++)

             {

                  TileInfo.Lods[i] = new Lod() {Resolution = resolution};

                  resolution /= 2;

             }

             //调用初始化事件

             base.Initialize();

         }

         ///返回指定切片的url

         public override stringGetTileUrl(int level, introw, int col)

         {

             returnbaseUrl1 + ra.Next(1, 7).ToString() + baseUrl2 + "L="+ level.ToString() + "&X=" +col.ToString() + "&Y=" +row.ToString();

            //returnbaseUrl + "L=" + level.ToString() + "&X=" +col.ToString() + "&Y=" + row.ToString();            

         }

    }