C# ArcScene IMarker3DSymbol

            IMarker3DSymbol pMarker3DSymbol = new Marker3DSymbolClass();
            string filePath = @"E:\TestSoft\WindowsFormsGis\bin\Release\1.3ds";
            IImport3DFile import3Dfile = new Import3DFileClass();
            pMarker3DSymbol.CreateFromFile(filePath);
            ISymbol pSymbol = pMarker3DSymbol as ISymbol;
            if (pSymbol == null)
            {
                System.Windows.Forms.MessageBox.Show("pSymbol == null");
            }

                             ISimpleRenderer pRender = new SimpleRendererClass();
             IGeoFeatureLayer pGFlayer = (IGeoFeatureLayer)layer;
                             pGFlayer.Renderer = (IFeatureRenderer)pUVRender;

                            axSceneControl1.SceneGraph.RefreshViewers();
            this.axSceneControl1.Refresh();

                            为什么不能符号化成功

这有很多可能，比如说你的模型文件本身是否合法，axSceneControl控件本身有没有问题，去掉try catch（如果有的话），看下报什么异常。

            axSceneControl1.SceneViewer.Redraw(true);
            axSceneControl1.Scene.SceneGraph.RefreshViewers();
            axSceneControl1.SceneGraph.RefreshViewers();

缺少一个刷新。。