Get parent of a part in a linked model

[a.sabatier]

Hi

I've created a part from a linked file and I'm trying to get the parent of that part.

I found that code that work when the parent is in the same document that the part but it returns "-1" when the parent is in the linked document.

Document documentlie = doc;

            //On crée la variable pour le document lié.

            foreach (Document dmt in uiapp.Application.Documents)

            {

                if (dmt != doc) documentlie = dmt;

            }

Element elt; 

Part elementpart = elt as Part;

ICollection<LinkElementId> lIds = elementpart.GetSourceElementIds();

LinkElementId lId = lIds.First<LinkElementId>();

ElementId parentElementId = lId.HostElementId;

TaskDialog.Show("parentElementId", parentElementId.ToString());//return the right id when the parent is in the same file and "-1" when it's in a linked document

Thanks for your help.

Alexandre

[jeremytammik · Accepted solution]

Dear Alexandre,

Thank you for your query.

GetSourceElementIds returns the ids of the elements from which a Part has been created by the PartMaker. There may be more than one source only if a merge is involved somewhere in the history of the Part.

In order to use it with a linked document, you probably have to check the LinkElementId lId first and see whether it represents a linked or local id.

As far as I can tell from the documentation, the HostElementId is designed to return -1 (representing an invalid element id, ElementId.Invalid) for linked elements.

For linked elements, you have to use the LinkedElementId property instead.

Look at the documentation of the LinkElementId members:

https://apidocs.co/apps/revit/2019/dccd1367-b891-92f1-f0d2-ece20af2b0cc.htm

• HostElementId - The id of the element in the host, or invalidElementId if there is a link.
• LinkedElementId - The id of the element in the link, or invalidElementId if no link.

I hope this helps.

Best regards,

Jeremy

[a.sabatier]

Thanks Jeremy

I just changed 

ElementId parentElementId = lId.HostElementId;

with

ElementId parentElementId = lId.LinkedElementId;

and it works.

Alexandre

[jeremytammik]

Lucky you!

And lucky me, for being able to guess the answer so easily  🙂

Cheers,

Jeremy