var beamBottomFaces = FaceUtils.GetBottomFaces(beam); //这个方法是自己封装的

if (null != beamBottomFaces && beamBottomFaces.Any())

{

    var beamLocationCurve = beam.Location as LocationCurve;

    var beamCurve = beamLocationCurve.Curve;

    if (beamCurve != null)

    {

         if (beamCurve is Line)

         {

              beamCurve = GetExtLocationCurve(beamCurve); //如果LocationCurve是Line，最好做个延伸算法来延长，不然有些梁因为扣减的话，locationCurve容易缺少一部分

         }

         var beamPoints = GetPoints(beamCurve, pointRange); //pointRange是取点间隔

         if (beamPoints != null && beamPoints.Any())

         {

              var floorDataList = GetBeamFloorsPairCore(beamBottomFaces, beamPoints, floors); //floors为建筑板

         }

    }

}

private Curve GetExtLocationCurve(Curve curve)

{

     XYZ dir0 = XYZ.Zero;

     XYZ dir1 = XYZ.Zero;

     if (curve is Line)

     {

          dir0 = (curve as Line).Direction.Negate();

          dir1 = (curve as Line).Direction;

     }

      Curve extCurve = Line.CreateBound(curve.GetEndPoint() + 1E3 * dir0, curve.GetEndPoint() + 1E3 * dir1);

      return extCurve;

}

private List<XYZ> GetPoints(Curve curve, double pointRange)

{

       var points = new List<XYZ>();

       var beamLength = curve.Length;

       var pointsNumber = beamLength % pointRange ==  ? ((beamLength / pointRange) - ) : Math.Floor((beamLength / pointRange));

       for(var i = ; i <= pointsNumber; i++)

       {

          var point = curve.Evaluate(pointRange * i, false);

          points.Add(point);

       }

       return points;

}

private List<KeyValuePair<Element, List<KeyValuePair<XYZ, double>>>> GetBeamFloorsPairCore(List<PlanarFace> beamBottomFaces, IEnumerable<XYZ> beamPoints, List<Element> floors)

{

      var floorDataList = new List<KeyValuePair<Element, List<KeyValuePair<XYZ, double>>>>();

      //寻找每一块结构梁下的板

      foreach (var floor in constructionFloors)

      {

         //获取该板的最上点坐标

         var floorTopFaces = FaceUtils.GetTopFaces(floor);

         if (null != floorTopFaces && floorTopFaces.Any())

         {

              var defaultFloorOriginZ = floorTopFaces.FirstOrDefault().Origin.Z;

              foreach (var tf in floorTopFaces)

              {

                   var originZ = tf.Origin.Z;

                   if (defaultFloorOriginZ <= originZ)

                   {

                       defaultFloorOriginZ = originZ;

                   }

              }

              var defaultBeamOriginZ = beamBottomFaces.FirstOrDefault().Origin.Z;

              foreach (var bf in beamBottomFaces)

              {

                   var originZ = bf.Origin.Z;

                   if (defaultBeamOriginZ >= originZ)

                   {

                       defaultBeamOriginZ = originZ;

                   }

              }

              //板在梁下面

              var isLower = defaultFloorOriginZ < defaultBeamOriginZ;

              if (isLower)

              {

                   var datalist = new List<KeyValuePair<XYZ, double>>();

                   //梁上一点能投影到板上

                   foreach (var point in beamPoints)

                   {

                       foreach (var tf in floorTopFaces)

                       {

                           var isProject = tf.Project(point);

                           if (null != isProject)

                           {

                               //投影到板上点的坐标

                               var projectPoint = isProject.XYZPoint;

                               //投影点到梁上点的距离

                               foreach (var bf in beamBottomFaces)

                               {

                                   var bp = bf.Project(projectPoint);

                                   if (null != bp)

                                   {

                                       var distance = bp.Distance;

                                       distance = UnitUtils.ConvertFromInternalUnits(distance, DisplayUnitType.DUT_MILLIMETERS);

                                       distance = Math.Floor(distance);

                                       var pointAndDistance = new KeyValuePair<XYZ, double>(projectPoint, distance);

                                       datalist.Add(pointAndDistance);

                                       break;

                                    }

                                }

                            }

                        }

                    }

                    if (datalist != null && datalist.Any())

                    {

                       var floorAndData = new KeyValuePair<Element, List<KeyValuePair<XYZ, double>>>(floor, datalist);

                       floorDataList.Add(floorAndData);

                    }

                }

           }

     }

     return floorDataList;

}