Revit api 创建族并加载到当前项目

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
 using Autodesk.Revit.UI;
 using Autodesk.Revit.DB;
 using Autodesk.Revit.Attributes;
 using Autodesk.Revit.ApplicationServices;

 namespace CreateFamily
 {
     [Transaction(TransactionMode.Manual)]
     public class Class1:IExternalCommand
     {
         public Result Execute(ExternalCommandData commandData, ref string message, ElementSet elements)
         {
             string rftPath = @"C:\ProgramData\Autodesk\RVT 2016\Family Templates\Chinese\公制柱.rft";
             UIApplication uiapp = commandData.Application;
             Application app = uiapp.Application;
             UIDocument uidoc = commandData.Application.ActiveUIDocument;
             Document doc = uidoc.Document;

             //创建族文件
             Document faDoc = app.NewFamilyDocument(rftPath);

             Transaction trans = new Transaction(faDoc, "Create Family");
             trans.Start();
             FamilyManager manager = faDoc.FamilyManager;
             //添加材质参数
             FamilyParameter mfp = manager.AddParameter("材质", BuiltInParameterGroup.PG_MATERIALS, ParameterType.Material, false);

             //创建拉伸
             CurveArrArray arry = GetCurves();
             SketchPlane skplane = GetSketchPlane(faDoc);
             Extrusion extrusion = faDoc.FamilyCreate.NewExtrusion(true, arry, skplane,  / 304.8);
             faDoc.Regenerate();

             //创建约束
             Reference topFaceRef = null;
             Options opt = new Options();
             opt.ComputeReferences = true;
             opt.DetailLevel = ViewDetailLevel.Fine;
             GeometryElement gelm = extrusion.get_Geometry(opt);
             foreach (GeometryObject gobj in gelm)
             {
                 if (gobj is Solid)
                 {
                     Solid s = gobj as Solid;
                     foreach (Face face in s.Faces)
                     {
                         if (face.ComputeNormal(new UV()).IsAlmostEqualTo(new XYZ(, , )))
                         {
                             topFaceRef = face.Reference;
                         }
                     }
                  }
             }
             View v = GetView(faDoc);
             Reference r =GetTopLevel(faDoc);
             Dimension d = faDoc.FamilyCreate.NewAlignment(v, r, topFaceRef);
             d.IsLocked = true;
             faDoc.Regenerate();

             //关联材质参数
             Parameter p = extrusion.get_Parameter(BuiltInParameter.MATERIAL_ID_PARAM);
             manager.AssociateElementParameterToFamilyParameter(p, mfp);

             trans.Commit();

             Family fa = faDoc.LoadFamily(doc);
             faDoc.Close(false);
             trans = new Transaction(doc, "CreateColumn");
             trans.Start();
             fa.Name = "我的柱";
             trans.Commit();
             return Result.Succeeded;
         }

         private CurveArrArray GetCurves()
         {
             double len =  / 304.8;

             XYZ p1 = new XYZ(-len, -len, );
             XYZ p2 = new XYZ(len, -len, );
             XYZ p3 = new XYZ(len, len, );
             XYZ p4 = new XYZ(-len, len, );

             Line l1 = Line.CreateBound(p1, p2);
             Line l2 = Line.CreateBound(p2, p3);
             Line l3 = Line.CreateBound(p3, p4);
             Line l4 = Line.CreateBound(p4, p1);
             CurveArrArray ary = new CurveArrArray();
             CurveArray arry = new CurveArray();
             arry.Append(l1);
             arry.Append(l2);
             arry.Append(l3);
             arry.Append(l4);
             ary.Append(arry);
             return ary;
         }

         private SketchPlane GetSketchPlane(Document doc)
         {
             FilteredElementCollector temc = new FilteredElementCollector(doc);
             temc.OfClass(typeof(SketchPlane));
             SketchPlane sketchPlane = temc.First(m => m.Name == "低于参照标高") as SketchPlane;
             return sketchPlane;
         }

         private View GetView(Document doc)
         {
             FilteredElementCollector viewFilter = new FilteredElementCollector(doc);
             viewFilter.OfClass(typeof(View));
             View v = viewFilter.First(m => m.Name == "前") as View;
             return v;
         }

         private Reference GetTopLevel(Document doc)
         {
             FilteredElementCollector temc = new FilteredElementCollector(doc);
             temc.OfClass(typeof(Level));
             Level lvl = temc.First(m => m.Name == "高于参照标高") as Level;
             return new Reference(lvl);
         }
     }
 }