void AddMarkerGraphics()
{
List<string> coordList = new List<string>(){"1346270,7357522", "8181982,2045495", "6011252,4383204"};
GraphicsLayer graphicsLayer = MyMap.Layers["MyGraphicsLayer"] as GraphicsLayer;
for (int i = 0; i < coordList.Count; i++)
{
string[] xy = coordList[i].Split(',');
MapPoint point = new MapPoint(Convert.ToDouble(xy[0]), Convert.ToDouble(xy[1]));
Graphic graphic = new Graphic()
{
Geometry = point,
Symbol = i > 0 ? RedMarkerSymbol : BlackMarkerSymbol
};
graphicsLayer.Graphics.Add(graphic);
}
}