AutoCAD.net: 求空间两曲线交点

引自：http://www.objectarx.net/bbs/archiver/?tid-410.html

using System;
using System.Collections.Generic;
using System.Text;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.Colors;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.EditorInput;
using Autodesk.AutoCAD.Geometry;
using Autodesk.AutoCAD.Runtime;
using AsApp = Autodesk.AutoCAD.ApplicationServices.Application;
using DsTM = Autodesk.AutoCAD.DatabaseServices.TransactionManager;
using Autodesk.AutoCAD.GraphicsInterface;
using Autodesk.AutoCAD.Interop;

namespace ObjectArxNet.Test
{
    /**//// <summary>
    /// 求空间两曲线交点
    /// </summary>
    public class Intersection
    {
        [CommandMethod("IntersectionTest")]
        public void IntersectionTest()
        {
            Editor m_ed = Application.DocumentManager.MdiActiveDocument.Editor;
            Database m_db = HostApplicationServices.WorkingDatabase;
            PromptEntityOptions m_peo = new PromptEntityOptions("\n请选择第一条曲线:");
            PromptEntityResult m_per = m_ed.GetEntity(m_peo);
            if (m_per.Status != PromptStatus.OK) { return; }
            ObjectId m_objid1 = m_per.ObjectId;

            m_peo = new PromptEntityOptions("\n请选择第二条曲线:");
            m_per = m_ed.GetEntity(m_peo);
            if (m_per.Status != PromptStatus.OK) { return; }
            ObjectId m_objid2 = m_per.ObjectId;

            using (Transaction m_tr = m_db.TransactionManager.StartTransaction())
            {
                Curve m_cur1 = (Curve)m_tr.GetObject(m_objid1, OpenMode.ForRead);
                Curve m_cur2 = (Curve)m_tr.GetObject(m_objid2, OpenMode.ForRead);

                Point3dCollection m_ints = new Point3dCollection();
                m_cur1.IntersectWith(m_cur2, Intersect.OnBothOperands, new Plane(), m_ints, 0, 0); //得出的所有交点在c1曲线上
                foreach (Point3d m_pt in m_ints)
                {
                    m_ed.WriteMessage("\n第一条曲线与第二条曲线交点:{0}", m_pt);
                }

                m_ed.WriteMessage("\n===");
                m_ints.Clear();
                m_cur2.IntersectWith(m_cur1, Intersect.OnBothOperands, new Plane(), m_ints, 0, 0); //得出的所有交点在c2曲线上
                foreach (Point3d m_pt in m_ints)
                {
                    m_ed.WriteMessage("\n第二条曲线与第条曲线一交点:{0}", m_pt);
                }
                m_tr.Commit();
            }
        }

    }
}