About family documents

Family

The Family object represents an entire Revit family. A Family Document is a Document that represents a Family rather than a Revit project.

Using the Family Creation functionality of the Revit API, you can create and edit families and their types. This functionality is particularly useful when you have pre-existing data available from an external system that you want to convert to a Revit family library.

API access to system family editing is not available.

Parameters

Family parameters can be accessed from the OwnerFamily property of a Family Document as the following example shows.

Code Region 13-2: Category of open Revit Family Document

// get the owner family of the family document.
Family family = familyDoc.OwnerFamily; 
Parameter param = family.get_Parameter(BuiltInParameter.FAMILY_WORK_PLANE_BASED);
// this param is a Yes/No parameter in UI, but an integer value in API
// 1 for true and 0 for false
int isTrue = param.AsInteger(); 
// param.Set(1); // set value to true.

Creating a Family Document

The ability to modify Revit Family documents and access family types and parameters is available from the Document class if the Document is a Family document, as determined by the IsFamilyDocument property. To edit an existing family while working in a Project document, use the EditFamily() functions available from the Document class, and then use LoadFamily() to reload the family back into the owner document after editing is complete. To create a new family document use Application.NewFamilyDocument():

Code Region 13-3: Creating a new Family document

// create a new family document using Generic Model.rft template
string templateFileName = @"C:\Documents and Settings\All Users\Application Data\Autodesk\RST 2011\Imperial Templates\Generic Model.rft";

Document familyDocument = application.NewFamilyDocument(templateFileName);
if (null == familyDocument)
{
        throw new Exception("Cannot open family document");
}

Nested Family Symbols

You can filter a Family Document for FamilySymbols to get all of the FamilySymbols loaded into the Family. In this code sample, all the nested FamilySymbols in the Family for a given FamilyInstance are listed.

Code Region 13-4: Getting nested Family symbols in a Family

public void GetLoadedSymbols(Autodesk.Revit.DB.Document document, FamilyInstance familyInstance)
{
        if (null != familyInstance.Symbol)
        {
                // Get family associated with this
                Family family = familyInstance.Symbol.Family;

                // Get Family document for family
                Document familyDoc = document.EditFamily(family);
                if (null != familyDoc && familyDoc.IsFamilyDocument == true)
                {
                        String loadedFamilies = "FamilySymbols in " + family.Name + ":\n";
                        FilteredElementCollector collector = new FilteredElementCollector(document);
                        ICollection<Element> collection = 
                                collector.OfClass(typeof(FamilySymbol)).ToElements();
                        foreach (Element e in collection)
                        {
                                FamilySymbol fs = e as FamilySymbol;
                                loadedFamilies += "\t" + fs.Name + "\n";
                        }

                        TaskDialog.Show("Revit",loadedFamilies);
                }
        }
}

About family documents