public static void CreateElementUniLine(string unparsed)
{
BD.DgnModel activeDgnModel = Program.ActiveDgnModel;
double uorPerMe = activeDgnModel.GetModelInfo().UorPerMaster;
var lines = new BG.DPoint3d[]
{
new BG.DPoint3d(0, 0),
new BG.DPoint3d(100 * uorPerMe, 0),
new BG.DPoint3d(100 * uorPerMe, 100 * uorPerMe),
new BG.DPoint3d(0, 100 * uorPerMe),
};
var curvePri = BG.CurvePrimitive.CreateLineString(lines);
BG.DEllipse3d circle = BG.DEllipse3d.FromCenterRadiusXY(new BG.DPoint3d(50 * uorPerMe, 50 * uorPerMe), 10 * uorPerMe);
var curvePriC = BG.CurvePrimitive.CreateArc(circle);
BG.CurveVector composeCurveVector = new BG.CurveVector(BG.CurveVector.BoundaryType.ParityRegion)
{
curvePri, curvePriC
};
var ele = BDE.DraftingElementSchema.ToElement(activeDgnModel, composeCurveVector, null);
ele.AddToModel();
}