AE保存地图文档—锁定冲突异常

                //确保布局视图中的所有元素都保存

                mapDoc.ReplaceContents((IMxdContents)axPageLayoutControl1.PageLayout);

                //处理异常关键三句代码

               IObjectCopy objectCopy = new ObjectCopyClass();
                mapControl.Map = (IMap)objectCopy.Copy(mapDoc.get_Map(0));               
                objectCopy = null;

                mapDoc.Save(mapDoc.UsesRelativePaths, false);
                mapDoc.Close();