Get CostDistance IGeoDataset as raster in C# ArcObjects

Question

I have a CostDistanceCode that works correctly. I cannot cast the IGeoDataset result into a raster. The last line returns a null raster. How can I resolve this?

            // Declare the output raster object
            //Note: Adjust the IDistanceOp.CostDistance method options to suit your applications need.         
            IDistanceOp distanceOp = new RasterDistanceOpClass();
            object object_missing1 = System.Type.Missing;
            object object_missing2 = System.Type.Missing;

            IFeatureClass in_source_Featuer2 = null;
            ClsGeneral.OpenFeatureClass(cmbSource.SelectedValue.ToString(), cmbSource.Text, out in_source_Featuer2);

            IRaster backlinkraster = new Raster();
            IGeoDataset g1 = in_source_Featuer2 as IGeoDataset;
            IGeoDataset g2 = rasOut as IGeoDataset;

            IGeoDataset geoDataset_output = distanceOp.CostDistance(g1, g2, ref object_missing1, ref object_missing2);
            IRasterDataSet raster_out = geoDataset_output  as IRasterDataSet ;

Answer 1

According to the API CostDistance() returns a Raster object which is a "a transient representation of raster data ". If you want to persist this object you should be able to save it to a RasterDataset using the ISaveAs2 interface.