m_mapx.ConvertCoord(&x,&y,&mapx,&mapy,miScreenToMap);
CMapXPoint point;
point.CreateDispatch(point.GetClsid());
point.Set(mapx,mapy);
CMapXFeature ft;
ft=m_mapx.GetFeatureFactory().CreateCircularRegion(miCircleTypeScreen, point, 3, miUnitDegree,100);
m_mapx.GetLayers().Item("畫圓層").AddFeature(ft);