UID pID = new  UIDClass();
            pID.Value = "esriCarto.MarkerNorthArrow";
            IMapSurround pMapSurround  = this.CreateSurround(pID,pEnv,"North Arrow",this.MapFrame,this.PageLayout.PageLayout);
            IMarkerNorthArrow pMarkerNorthArrow = pMapSurround as IMarkerNorthArrow; //QI 
            ICharacterMarkerSymbol pCharacterMarkerSymbol = pMarkerNorthArrow.MarkerSymbol as ICharacterMarkerSymbol; //clones the symbol 
            pCharacterMarkerSymbol.CharacterIndex = 167 ;//change the symbol 
            pCharacterMarkerSymbol.Color = GeoUtilities.CreateColor (0,0,0);
            pCharacterMarkerSymbol.Angle = 0;
            pCharacterMarkerSymbol.Size = 100;
            pMarkerNorthArrow.MarkerSymbol = pCharacterMarkerSymbol;//'set it back  
            
//            pEnv.PutCoords(1, 1, 3.4, 2.4);
//            pID.Value = "esriCarto.Legend";//增加legend
//            pMapSurround = CreateSurround(pID, pEnv, "Legend", this.MapFrame,this.PageLayout.PageLayout); //Refresh the graphics 
           
        }
        public IMapSurround CreateSurround(UID pID, IEnvelope pEnv,string strName,IMapFrame pMapFrame,IPageLayout pPageLayout)
        {
            IGraphicsContainer pGraphicsContainer = pPageLayout as IGraphicsContainer;
            IActiveView pActiveView = pPageLayout as IActiveView;
            IMapSurroundFrame  pMapSurroundFrame = pMapFrame.CreateSurroundFrame(pID, null) ;//MapSurroundFrames are related to MapFrames MapFrames hold Maps
            pMapSurroundFrame.MapSurround.Name = this.ElementNamePrefix+strName; //Set the geometry of the MapSurroundFrame to give it a location 
            //Activate it and add it to the PageLayout's graphics container
            IElement pElement = pMapSurroundFrame as IElement;  //MapSurrounds are held in a MapSurroundFram
            pElement.Geometry = pEnv;
            pElement.Activate(pActiveView.ScreenDisplay); //'Allow the legend frame size to be altered after the legend has been  'added to the GraphicsContainer 
            ITrackCancel PTrack = new CancelTrackerClass();
            pElement.Draw(pActiveView.ScreenDisplay, PTrack );
            pGraphicsContainer.AddElement(pElement, 0 );
            //Re-apply the change to the Legend MapSurroundFrame Geometry 
            //pElement.Geometry = pEnv ;
            return pMapSurroundFrame.MapSurround;
        }