ArcGIS for SilverLight之FindGraphicsInHostCoordinates
用DrawObject画框,并选中框框内的图元: //fLayer为FeatureLayer
double x1, y1, x2, y2;
mapControl.MapToScreen(rc.XMin, rc.YMin, out x1, out y1);
mapControl.MapToScreen(rc.XMax, rc.YMax, out x2, out y2);
//需要将屏幕坐标点转到Ap