Geodatabase - 打开栅格数据

打开栅格数据

　　和打开要素类的方式类似,打开栅格数据集需要用 IRasterWorkspace,如

 1 //获得栅格工作空间(普通目录).

 2         public ESRI.ArcGIS.DataSourcesRaster.IRasterWorkspace GetRasterWorkspace(string rasterWorkspacePath) {

 3             ESRI.ArcGIS.Geodatabase.IWorkspaceFactory wsf = new ESRI.ArcGIS.DataSourcesRaster.RasterWorkspaceFactoryClass();    //使用RasterWorkspaceFactoryClass.

 4             ESRI.ArcGIS.Geodatabase.IWorkspace ws = wsf.OpenFromFile(rasterWorkspacePath, 0);

 5             ESRI.ArcGIS.DataSourcesRaster.IRasterWorkspace rws = (ESRI.ArcGIS.DataSourcesRaster.IRasterWorkspace)ws;

 6             return rws;

 7         }

 8 

 9         /// <summary>

10         /// 打开栅格数据集(普通目录).

11         /// </summary>

12         /// <param name="foldName">目录名称(普通目录),如,foldName="G:\doc\gis\1.400\data\raster".</param>

13         /// <param name="fileName">栅格数据集的名称,如fileName="srtm_58_09.tif"</param>

14         /// <returns></returns>

15         public ESRI.ArcGIS.Geodatabase.IRasterDataset OpenRasterDataset(string foldName, string fileName) {

16             ESRI.ArcGIS.DataSourcesRaster.IRasterWorkspace rws = GetRasterWorkspace(foldName);

17             return rws.OpenRasterDataset(fileName);

18         }

19 

20         //获得栅格工作空间(数据库中).

21         //如rasterWorkspaceExPath="G:\doc\gis\1.400\data\pdb.mdb"

22         public ESRI.ArcGIS.Geodatabase.IRasterWorkspaceEx GetRasterWorkspaceEx(string rasterWorkspaceExPath) {

23             ESRI.ArcGIS.Geodatabase.IWorkspaceFactory wsf = new ESRI.ArcGIS.DataSourcesGDB.AccessWorkspaceFactoryClass();   //使用专门数据库.

24             ESRI.ArcGIS.Geodatabase.IWorkspace ws = wsf.OpenFromFile(rasterWorkspaceExPath, 0);

25             ESRI.ArcGIS.Geodatabase.IRasterWorkspaceEx rwsEx = (ESRI.ArcGIS.Geodatabase.IRasterWorkspaceEx)ws;

26             return rwsEx;

27         }

28 

29         /// <summary>

30         /// 打开栅格数据集(数据库中)

31         /// </summary>

32         /// <param name="rasterWorkspaceEx"></param>

33         /// <param name="rasterDatasetName">栅格数据集名称,如"rds"</param>

34         /// <returns></returns>

35         public ESRI.ArcGIS.Geodatabase.IRasterDataset OpenRasterDataset(ESRI.ArcGIS.Geodatabase.IRasterWorkspaceEx rasterWorkspaceEx, string rasterDatasetName) {

36             return rasterWorkspaceEx.OpenRasterDataset(rasterDatasetName);

37         }

 

需要指出的是,当我们的数据是存储在SDE数据库,FileGeodatabase或PersonalGeodatabase时,要用IRasterWorkspaceEx,而不是IRasterWorkspace.

IRasterWorkspace与IRasterWorkspaceEx的区别

　　　　1)IRasterWorkspace主要是用来读取以文件格式存储在本地的栅格数据.

　　　　2)IRasteWorkspaceEx接口主要是用来读取GeoDatabase中的栅格数据集和栅格目录.

 

打开栅格目录

　　打开栅格目录需要用IRasterWorkspaceEx,可以从以上(打开栅格数据集的第20~27行获取IRasterWorkspaceEx对象,然后通过OpenRasterCatalog获取.如

1 /// <summary>

2         /// 打开栅格目录.

3         /// </summary>

4         /// <param name="rasterWorkspaceEx"></param>

5         /// <param name="rasterCatalogName">栅格目录名,如rasterCatalogName="r_catalog"</param>

6         /// <returns></returns>

7         public ESRI.ArcGIS.Geodatabase.IRasterCatalog OpenRasterCatalog(ESRI.ArcGIS.Geodatabase.IRasterWorkspaceEx rasterWorkspaceEx, string rasterCatalogName) {

8             return rasterWorkspaceEx.OpenRasterCatalog(rasterCatalogName);

9         }

 打开栅格目录中的数据

1 //打开栅格目录中的数据.

2         ESRI.ArcGIS.Geodatabase.IRasterDataset GetRasterCatalogItem(ESRI.ArcGIS.Geodatabase.IRasterCatalog rasterCatalog, int objectId) {

3             ESRI.ArcGIS.Geodatabase.IFeatureClass fc = (ESRI.ArcGIS.Geodatabase.IFeatureClass)rasterCatalog;

4             ESRI.ArcGIS.Geodatabase.IRasterCatalogItem rCataItem = (ESRI.ArcGIS.Geodatabase.IRasterCatalogItem)fc.GetFeature(objectId);

5             return rCataItem.RasterDataset;

6         }