Revit API取得系统族普通族几何信息的方法

系统族，可以直接转化为对应的类(Wall,Duct)然后取得几何信息，普通族需要转化为FamilyInstance

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Forms;

using Autodesk.Revit.DB;
using Autodesk.Revit.UI;
using Autodesk.Revit.ApplicationServices;
using Autodesk.Revit.Attributes;

using Autodesk.Revit.DB;


[TransactionAttribute(Autodesk.Revit.Attributes.TransactionMode.Manual)]
public class GetWallBFace : IExternalCommand
{
  public Result Execute(ExternalCommandData commandData, ref string messages, ElementSet elements)
  {

    UIApplication app = commandData.Application;
    Document doc = app.ActiveUIDocument.Document;

    //select a wall      
    Reference ref1 = app.ActiveUIDocument.Selection.PickObject(Autodesk.Revit.UI.Selection.ObjectType.Element, "Please pick a wall");
    Element elem = doc.GetElement(ref1);
    Wall wall = elem as Wall;

    Options opt = new Options();
    opt.ComputeReferences = true;
    opt.DetailLevel = Autodesk.Revit.DB.DetailLevels.Medium;

    GeometryElement e = wall.get_Geometry(opt);//系统族的Geometry可以直接获取

    foreach (GeometryObject obj in e.Objects)
    {
      Solid solid = obj as Solid;
      if (solid != null && solid.Faces.Size > 0)//实体必须做这样的判断，因为有可能是假的。        
        FindBottomFace(solid);
    }

    return Result.Succeeded;
  }

  Face FindBottomFace(Solid solid)
  {
    PlanarFace pf = null;
    foreach (Face face in solid.Faces)
    {
      pf = face as PlanarFace;//转化为立面平面
      if (null != pf)
      {
        //判断向量的方法：转化为Normal然后以绝对值判断(0,0,-1)
        if (Math.Abs(pf.Normal.X) < 0.01 && Math.Abs(pf.Normal.Y) < 0.01 && pf.Normal.Z < 0)
        {
          TaskDialog.Show("Wall Bottom Face", "Area is " + pf.Area.ToString() + "; Origin = (" + pf.Origin.X.ToString() + "  " + pf.Origin.Y.ToString() + "  " + pf.Origin.Z.ToString() + ")");

          break;
        }
      }
    }
    return pf;
  }

}


[TransactionAttribute(Autodesk.Revit.Attributes.TransactionMode.Manual)]
public class GetColumnBottomFace : IExternalCommand
{
  public Result Execute(ExternalCommandData commandData, ref string messages, ElementSet elements)
  {

    UIApplication app = commandData.Application;
    Document doc = app.ActiveUIDocument.Document;

    //select a column      
    Reference ref1 = app.ActiveUIDocument.Selection.PickObject(Autodesk.Revit.UI.Selection.ObjectType.Element, "Please pick a column");
    Element elem = doc.GetElement(ref1);
    FamilyInstance column = elem as FamilyInstance;//柱是族实例

    Options opt = new Options();
    opt.ComputeReferences = true;
    opt.DetailLevel = Autodesk.Revit.DB.DetailLevels.Medium;

    GeometryElement e = column.get_Geometry(opt);

    foreach (GeometryObject obj in e.Objects)
    {
      //被切割的族有Solid
      if (obj is Solid)
      {
        Solid solid = obj as Solid;
        FindBottomFace(solid);
      }
      else if (obj is GeometryInstance)//取得族实例几何信息的方法
      {
        GeometryInstance geoInstance = obj as GeometryInstance;
        GeometryElement geoElement = geoInstance.GetInstanceGeometry();
        foreach (GeometryObject obj2 in geoElement.Objects)
        {
          if (obj2 is Solid)
          {
            Solid solid2 = obj2 as Solid;
            if (solid2.Faces.Size > 0)
              FindBottomFace(solid2);
          }
        }
      }
    }
    return Result.Succeeded;
  }

  Face FindBottomFace(Solid solid)
  {
    PlanarFace pf = null;
    foreach (Face face in solid.Faces)
    {
      pf = face as PlanarFace;
      if (null != pf)
      {
        if (Math.Abs(pf.Normal.X) < 0.01 && Math.Abs(pf.Normal.Y) < 0.01 && pf.Normal.Z < 0)
        {
          TaskDialog.Show("column Bottom Face", "Area is " + pf.Area.ToString() + "; Origin = (" + pf.Origin.X.ToString() + "  "  +pf.Origin.Y.ToString() + "  " + pf.Origin.Z.ToString() + ")");
          
          break;
        }
      }
    }
    return pf;
  }

}

[TransactionAttribute(Autodesk.Revit.Attributes.TransactionMode.Manual)]
public class GetWallBottomFace : IExternalCommand
{
  public Result Execute(ExternalCommandData commandData, ref string messages, ElementSet elements)
  {
    UIApplication app = commandData.Application;
    Document doc = app.ActiveUIDocument.Document;

    //select a wall
    Reference ref1 = app.ActiveUIDocument.Selection.PickObject(Autodesk.Revit.UI.Selection.ObjectType.Element, "Pick a wall");
    Element elem = doc.GetElement(ref1);
    Wall wall = elem as Wall;

    Options opt = new Options();
    opt.ComputeReferences = true;
    opt.DetailLevel = Autodesk.Revit.DB.DetailLevels.Medium;

    GeometryElement e = wall.get_Geometry(opt);
    foreach (GeometryObject obj in e.Objects)
    {
      Solid solid = obj as Solid;
      if (solid != null && solid.Faces.Size > 0)
      {
        FindBottomFaces(solid);
      }
    }

    return Result.Succeeded;
  }

  Face FindBottomFaces(Solid solid)
  {
    PlanarFace pf = null;
    foreach (Face face in solid.Faces)
    {
      pf = face as PlanarFace;
      if(null != pf)
      {
        if(Math.Abs(pf.Normal.X) < 0.01 && Math.Abs(pf.Normal.Y) < 0.01 && pf.Normal.Z < 0)
        {
          TaskDialog.Show("the bottom face's area is ",  pf.Area.ToString());
        }
      }
    }
    return pf;
  }
}

end