ArcEngine加载和保存3dd文件

ArcEngine提供了加载3dd文件的方法，却没有开放保存3dd文件的接口，通过查找资料，主要是采用二进制段实现了3dd文件的保存和加载，但是用这种方法保存的3dd文件其实是“伪”3dd文件，在ArcGlobe下是打不开的。下面是源代码：

        private void button_Open3dd_Click (object sender,EventArgs e)
        {
            try
            {
                ClearGlobe();
                OpenFileDialog open3ddDialog = new OpenFileDialog();
                open3ddDialog.Title = "打开3dd文件";
                open3ddDialog.Filter = "3dd文件(*.3dd)|*.3dd";

                if(open3ddDialog.ShowDialog() == DialogResult.OK)
                {
                    if(axGlobeControl1.Check3dFile(open3ddDialog.FileName))
                    {
                        axGlobeControl1.Load3dFile(open3ddDialog.FileName);
                        
                    }
                    else
                    {
                        IObjectStream pObjectStream = new ObjectStreamClass();
                        IMemoryBlobStream pMemoryBlobStream = new MemoryBlobStreamClass();
                        pMemoryBlobStream.LoadFromFile(open3ddDialog.FileName);
                        IPersistStream pPersistStream = m_globeControl.Globe as IPersistStream;
                        pObjectStream.Stream = pMemoryBlobStream;
                        pPersistStream.Load(pObjectStream);
                        
                    }

                }
                else
                {
                    return;
                }
            }
            catch(System.Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void button_Save3dd_Click (object sender,EventArgs e)
        {

            try
            {
                SaveFileDialog save3ddDialog = new SaveFileDialog();
                save3ddDialog.Title = "保存3dd文件";
                save3ddDialog.Filter = "3dd文件(*.3dd)|*.3dd";
                save3ddDialog.FileName = "test.3dd";
                if (save3ddDialog.ShowDialog()==DialogResult.OK)
                {

                    IMemoryBlobStream pMemoryBlobStream = new MemoryBlobStream();
                    IObjectStream pObjectStream = new ObjectStream();
                    pObjectStream.Stream = pMemoryBlobStream;
                    IPersistStream pPersistStream = m_globeControl.Globe as IPersistStream;
                    pPersistStream.Save(pObjectStream,1);
                    pMemoryBlobStream.SaveToFile(save3ddDialog.FileName);
                }
                else
                {
                    return;
                }
            }
            catch (System.Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

还有需要注意的问题：如果在加载3dd时，当前globecontrol中有图层存在的话，会出现闪退，我在这里只是简单的把当前globe中的所有图层清空（ClearGlobe函数），也可以采用ArcGlobe的方式写一个提示对话框的方式来处理，这样就不会出现闪退了