方法一.
IRasterCatalog rasterCatalog= rasterWorkspaceEx.OpenRasterCatalog(RasterCatalogName)
ITable table = rasterCatalog as ITable;
ICursor cursor = table.search(null,false);
IRow row = cursor.NextRow();
While(row != null)
{
IRasterCatalogItem rasterCatalogItem = row as IRasterCatalogItem;
IRasterDataset rasterDataset = rasterCatalogItem.RasterDataset;
row = cursor.NextRow();
}