如何在 Revit api c# 中将创建的墙类型转换为族文件

Question

I am working on a project in Revit API where I need to

1. create wall,
2. create a new wall type with materials
3. Add type parameters to wall and materials
4. Generate rfa file for the same

I did the first 3 parts, but when I filter to extract family

FilteredElementCollector collector = new FilteredElementCollector(doc);
Family famType = collector.OfClass(typeof(Family)).FirstOrDefault(x => x.Name == "Basic Wall") as Family;

This returns null.
So I tried with Family Instance since I also created the wall.

 List<FamilyInstance> list = new FilteredElementCollector(RevitData.Document).OfCategory(BuiltInCategory.OST_Walls).OfClass(typeof(FamilyInstance)).Cast<FamilyInstance>().ToList<FamilyInstance>();

But this also returned null

In the attached image, the Project Browser, shows the "Test wall" in Basic Wall Family type.

Can we actually extract wall type as.rfa?

If this is possible, can someone guide me through this.

Thank You

Answer 1

Walls are System Families and you cannot save them as a *.rfa File.

Your collector is not working because you are using the wrong classes in the filter, the class Wall or WallType is the correct one.

To exchange WallTypes between projects, you can transfer Project Standards -> Wall Types, however there is no API for that. As alternative you could use the method ElementTransformUtils.CopyElements() to copy the Wall or WallType, or try to regenerate the WallType in the target Document using an existing WallType and the Duplicate method setting all the Parameters as in the source Document.