public void CreateAndUpdate(Workspace workspace, Datasource datasource)
{
   // 取出数据源中名为 "D71244_IMG1" 和 "D71244_IMG2" 的影像数据集（DatasetImage）
   DatasetImage datasetImage1 = (DatasetImage)datasource.Datasets["D71244_IMG1"];
   DatasetImage datasetImage2 = (DatasetImage)datasource.Datasets["D71244_IMG2"];

   // 删除数据源里可能存在的名为"Del_D71244_IMG1"的影像数据集
   String name = "Del_" + datasetImage1.Name;
   if (!datasource.Datasets.IsAvailableDatasetName(name))
   {
       datasource.Datasets.Delete(name);
    }

   // 设置所要创建的影像数据集的相关信息，如范围、像素格式、编码方式等
   Rectangle2D bound = new Rectangle2D();
   bound.Bottom = 0;
   bound.Left = 66.5;
   bound.Right = 105.5;
   bound.Top = 54;
   DatasetImageInfo datasetImageInfo = new DatasetImageInfo();
   datasetImageInfo.Name = name;
   datasetImageInfo.BlockSizeOption = 128;
   datasetImageInfo.Bounds = bound;
   datasetImageInfo.Height = datasetImage1.Height;
   datasetImageInfo.Width = datasetImage1.Width + datasetImage2.Width;
   datasetImageInfo.PixelFormat = datasetImage1.PixelFormat;
   datasetImageInfo.EncodeType = datasetImage1.EncodeType;

   // 创建影像数据集
   DatasetImage datasetImage = datasource.Datasets.Create(datasetImageInfo);

   // 设置创建好的影像数据集的投影信息
   datasetImage.PrjCoordSys = datasetImage1.PrjCoordSys;        

   // 分别用名为 "D71244_IMG1" 和 "D71244_IMG1" 这两个影像数据集更新影像数据集          
   Boolean b1 = datasetImage.Update(datasetImage1);
   Boolean b2 = datasetImage.Update(datasetImage2);
}