We have an IfcLabel which contains an apostrophe and it’s breaking at least two viewers that we know of. How do we escape “special” characters in IFC with a guarantee that viewers will handle un-escaping?
Hey @ian,
I know we have only a couple resources that address this:
- An implementation Agreement for IFC2x3: CV-2x3-132 (buildingsmart.org)
- An Implementation Guidance page: IFC String Encoding - buildingSMART Technical
Maybe @Evandro, @GeorgDangl, @linhard, or @mweise can help? I think this issue might be part of certification.
For clarity:
From 10303 21 we can read:
6.4.3.1 String structure
… Within a string, a single apostrophe shall be encoded as two consecutive apostrophes
I must say that I’ve personally never have encountered issues with this in any implementation I’m aware of.
Thanks @aothms.
As far as I can tell, you mean ISO 10303 part 21, which is a paywalled iso standard that a developer can’t access. Yes, they could spend the money and buy the standard, and look up the section on string encoding, but they’re probably not going to do it.
I agree, I’ve created an issue to improve IfcLabel/IfcText etc. · Issue #476 · buildingSMART/IFC4.3.x-development · GitHub
For reference, this is a great link 
https://www.steptools.com/stds/step/IS_final_p21e3.html#clause-6-4-3
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