Hi, as the title described, i am eager to  get the control points of a given surface.

  we carefully examinned the API help, only the function of GetBSurfParams/GetBSurfParams2 have been found.

               IFace2 tface = (IFace2)tfaces.GetValue(i);

               ISurface tsurface = tface.IGetSurface();

                double[] vp0 = new double[11];

                bool sense = false;

                double[] uv_range = new double[4];

                try

                {

                      Array ret_vals1 = (Array)(tsurface.GetBSurfParams2(true, true, vp0, 0.01, out sense));//(true,vp0));//

                }

                catch (System.Exception e1)

                {

                 // error triggered, because of none param has got.

                }

  We aim to get all control points of each suface, even not a b-spline suface, of a given solid body.   hope for your replay. thanks