Problem with LoadFamily method

[sean_dodsworth]

Hi All,

I'm having trouble using the Document.LoadFamily method to load a family when an older version of the family exists in the model.

My code looks like this:

public class FamilyLoadOptions : IFamilyLoadOptions
    {
        public bool OnFamilyFound(bool familyInUse, out bool overwriteParameterValues)
        {
            overwriteParameterValues = true;
            return true;
        }

        public bool OnSharedFamilyFound(Family sharedFamily, bool familyInUse, out FamilySource source, out bool overwriteParameterValues)
        {
            source = FamilySource.Family;
            overwriteParameterValues = true;
            return true;
        }

    }


Family loadedFamily = null;

var success = doc.LoadFamily(localPath, new FamilyLoadOptions(), out loadedFamily);

When the family already exists in the model success is always false and loadedFamily is always null.

Also when I try to debug the FamilyLoadOptions neither of its methods are every accessed.

Thanks in advance,

Sean

[aignatovich · Accepted solution]

Hi, Sean!

Did you try to change anything in your family before loading it into the project? If nothing changed, Revit will not load it to the document

[sean_dodsworth]

Yeah you're right, the family I was loading in must have been unchanged even though I had copied it to a different location.

Out of interest how does Revit know if one family is the same as another? Does it actually compare them element by element?

[aignatovich]

Don't know exactly, may be it just compares the hash of the families contents

[jeremytammik]

Dear Sean,

Thank you for your query, and to Alexander for his succinct, precise, complete answer.

Here are some previous discussions of thsis topic:

• Reloading a Family -- http://thebuildingcoder.typepad.com/blog/2011/06/reloading-a-family.html
• Reloading a Family Again -- http://thebuildingcoder.typepad.com/blog/2011/10/reloading-a-family-again.html
• Modifying, Saving and Reloading Families -- http://thebuildingcoder.typepad.com/blog/2014/09/modifying-saving-and-reloading-families.html

I hope this helps.

Best regards,

Jeremy

[sean_dodsworth]

Hi Jeremy,

I did try searching but didn't find the links you just posted.

This one is exactly what I was looking for: http://thebuildingcoder.typepad.com/blog/2011/10/reloading-a-family-again.html

It would be great if the SDK documentation for the LoadFamily method included that bit of information.

- Sean