AE 栅格处理

 由RasterDataset得到RasterLayer

RasterDataset->RasterLayer
 IRasterLayer pRasterLayer = new RasterLayerClass(); 

            pRasterLayer.CreateFromDataset(pRasterDataset); 

            axMapControl1.Map.AddLayer(pRasterLayer as ILayer); ;

由RasterLayer 得到RasterDataset

RasterLayer->RasterDataset
 IRasterLayer myrasterlayer = MapControl.Map.Layer[index] as IRasterLayer;
                IRaster myRaster = myrasterlayer.Raster;
                IRasterBandCollection myRasterBandCollection = myRaster as IRasterBandCollection;
                IRasterBand myRasterBand = myRasterBandCollection.Item();
                IRasterDataset myRasterDataset = myRasterBand as IRasterDataset;