CAD drawing flag parameter (com interface)

Implemented in C # code description:

private void DrawFlag(object sender, EventArgs e)
{
    MxDrawResbuf param;
    param = new MxDrawResbuf();
    MxDrawPoint point;
    point = new MxDrawPoint();

    point.x = 100;
    point.y = 100;

    param.AddPoint(point);

    MxDrawResbuf ret;

    ret = (MxDrawResbuf)axMxDrawX1.CallEx("ExApp_AddFlag", param);

    MessageBox.Show(ret.AtLong(1).ToString());
}

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