ao对象如geometry的保存

  private static bool FileToBlob(IEnvelope pEnvelope)

        {

            try

            {

                IPersistStream pPersistStream = pEnvelope as IPersistStream;

                IMemoryBlobStream pMemoryBlobStream = new MemoryBlobStreamClass();

                pPersistStream.Save(pMemoryBlobStream, 0);

                IWorkspaceFactory pWorkspaceFactory = new AccessWorkspaceFactoryClass();

                IWorkspace pWorkspace = pWorkspaceFactory.OpenFromFile(@"E:/义乌实验数据.mdb", 0);

                IFeatureWorkspace pFeatureWorkspace = pWorkspace as IFeatureWorkspace;

                ITable pTable = pFeatureWorkspace.OpenTable("geo");

                IRow pRow = pTable.CreateRow();

                int d = pRow.Fields.FindField("FW");

                pRow.set_Value(d, pMemoryBlobStream);

                pRow.Store();

                return true;

            }

            catch 

            {

                return false;

            }

        }

        private void   Load2()

        {

            IWorkspaceFactory pWorkspaceFactory = new AccessWorkspaceFactoryClass();

            IWorkspace pWorkspace = pWorkspaceFactory.OpenFromFile(@"E:/义乌实验数据.mdb", 0);

            IFeatureWorkspace pFeatureWorkspace = pWorkspace as IFeatureWorkspace;

            ITable pTable = pFeatureWorkspace.OpenTable("geo");

            ICursor pCursor = pTable.Search(null, false);

            IRow pRow = pCursor.NextRow();

            if (pRow == null) return;

            IMemoryBlobStream pMemoryStream = pRow.get_Value(pRow.Fields.FindField("FW")) as IMemoryBlobStream;

            IEnvelope pEnvelope = new EnvelopeClass();

            IPersistStream pPersist = pEnvelope as IPersistStream;

            pPersist.Load(pMemoryStream);

            axMapControl1 .Extent =pEnvelope ;

        }