Adding a marker symbol to a MapControl

Question

How do I add a marker symbol to an ArcGIS Engine MapControl at a specific coordinate?

Answer 1

    /// <summary>
    /// Places a marker on a map at an X and Y position.
    /// </summary>
    /// <param name="map">The map to place the dot on.</param>
    /// <param name="mapX">The X coordinate for the dot.</param>
    /// <param name="mapY">The Y coordinate for the dot.</param>
    /// <param name="markerSymbol">An IMarkerSymbol object describing the highlight symbol.</param>
    public static void DropMarkerOnMap(IMap map, double mapX, double mapY,
        IMarkerSymbol markerSymbol)
    {
        IActiveView av = (IActiveView) map;
        IGraphicsContainer gc = av.GraphicsContainer;
        IPoint pt = new PointClass();
        pt.X = mapX;
        pt.Y = mapY;
        IMarkerElement ptElem = new MarkerElementClass();
        ptElem.Symbol = markerSymbol;
        IElement elem = (IElement) ptElem;
        elem.Geometry = pt;
        gc.AddElement(elem, 0);
        av.PartialRefresh(esriViewDrawPhase.esriViewGraphics, null, av.Extent);
    }