« Group My Own Commands in the Ribbon | Main | Updating Properties and Announcing Revit LT »

September 05, 2012

Comments

Hi,

I am using the 2014 SDK's Revit::IFC::Export::Utility::GUIDUtil::CreateGUID method to create IFCGuid for an element, but it always throws an nullargument exception ... any ideas on that ?

Thank you.

Is the ID unique across multiple installations of revit in multiple firms. We have a situation where 5 firms are generating content and it will eventually be merged into one IFC data set. What are the chances that there will be duplicate ID's?

I need some clarification on exactly what the IFC GUID is; is it simply a link the the bsDD or does it contain information on the BIM object that it's referencing?

Dear Megan,

First of all, thank you for submitting your question here as a comment for all to share and participate in, instead of a private email message.

I do not know what you mean by bsDD.

Strictly speaking, Revit has no such thing as an IFC GUID.

Each Revit element is always equipped with two identifiers, the element id and the unique id. A third identifier for exporting the element to other file formats can be generated by the ExportUtils.GetExportId method. That is what we referred to as IFC GUID above.

The Revit element unique id uniquely identifies the building element across all projects and models. The unique id consists of a standard GUID plus an additional so-called epoch id.

The element id is a simple integer number and is only unique within the individual project file.

The export id or IFC GUID maps to the Revit element unique id and also uniquely references the building element. It is not identical to the unique id, though.

I hope this clarifies.

For further information and how to convert between these formats, please refer to the discussion above and the links it contains.

Cheers, Jeremy.

Dear Shaun,

Sorry for the late answer.

The chances of duplicate ids are almost if not exactly zero, as far as I know, for all elements that are newly generated.

The only danger that can arise is if these companies copy files back and forth and start new projects based on files that already contain some elements. Those elements would obviously have the same unique ids.

I hope this clarifies.

Cheers, Jeremy.

Dear Waleed,

Sorry for the late answer.

I would suggest debugging the method in question and exploring exactly what happens interactively in the debugger.

That should show you what object is causing the problem right away.

Cheers, Jeremy.

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Working...
Your comment could not be posted. Error type:
Your comment has been posted. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.

Working...

Post a comment

Your Information

(Name and email address are required. Email address will not be displayed with the comment.)

Jeremy Tammik

AboutTopicsIndexSource