# \#userdata

**URL:** https://discourse.mcneel.com/tag/userdata/1208.md

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## [Custom Objects 2026](https://discourse.mcneel.com/t/custom-objects-2026/214657)

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**Author:** [@bobtato](https://discourse.mcneel.com/u/bobtato)\
**Replies:** 2\
**Last updated:** [January 22, 2026, 2:10am UTC](https://discourse.mcneel.com/t/custom-objects-2026/214657 "2026-01-22T02:10:02Z")

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There are a few older threads about this, but I don’t know the current status. I would like to create a plugin to work with custom objects, and I’d like to be able to develop it on a Mac. Previous answers suggest that …

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## [Custom.UserData wiped when extending geometry](https://discourse.mcneel.com/t/custom-userdata-wiped-when-extending-geometry/211684)

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**Author:** [@Frusciante](https://discourse.mcneel.com/u/Frusciante)\
**Replies:** 2\
**Last updated:** [October 29, 2025, 9:43pm UTC](https://discourse.mcneel.com/t/custom-userdata-wiped-when-extending-geometry/211684 "2025-10-29T21:43:57Z")

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Hello fellow grasshoppers, I’m encountering a frustrating issue with Rhino.Geometry.Curve objects losing their custom data upon modification, and I’m hoping to tap into the community’s expertise! The Setup I have a spe…

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## [Failing to read/write UserData from Object.Attribute](https://discourse.mcneel.com/t/failing-to-read-write-userdata-from-object-attribute/194298)

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**Author:** [@Alex61](https://discourse.mcneel.com/u/Alex61)\
**Replies:** 2\
**Last updated:** [November 4, 2024, 11:55pm UTC](https://discourse.mcneel.com/t/failing-to-read-write-userdata-from-object-attribute/194298 "2024-11-04T23:55:26Z")

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I’m trying to save an attribute to Object.Attributes.UserData. The data is saved during the session, but when reloading the .3dm file it is not. (The color change to Attributes.ObjectColor is saved, but the custom dat ad…

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## [Failing to Read UserData](https://discourse.mcneel.com/t/failing-to-read-userdata/183586)

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**Author:** [@EricM](https://discourse.mcneel.com/u/EricM)\
**Replies:** 8\
**Last updated:** [June 13, 2024, 12:05am UTC](https://discourse.mcneel.com/t/failing-to-read-userdata/183586 "2024-06-13T00:05:42Z")

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Hey @dale \< FYI - My code is F#, but I’m using dotPeek on the .rhp file to get the equivalent C#. If a variable name is generated, I do a quick notepad find and replace with something friendlier.\> I’m adding a History…

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## [User text attributes character limit](https://discourse.mcneel.com/t/user-text-attributes-character-limit/166356)

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**Author:** [@Benjamin\_Paolo\_Fortu](https://discourse.mcneel.com/u/Benjamin_Paolo_Fortu)\
**Replies:** 0\
**Last updated:** [September 27, 2023, 10:56pm UTC](https://discourse.mcneel.com/t/user-text-attributes-character-limit/166356 "2023-09-27T22:56:26Z")

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I’m looking to write a JSON string to a user attribute and was wondering what the character limit was for attributes attached to objects. I’m testing it now, but want to get a gauge of how much leeway I have before I hit…

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## [Feature request: add user data as input for all Karamba components](https://discourse.mcneel.com/t/feature-request-add-user-data-as-input-for-all-karamba-components/161220)

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**Author:** [@Jurriaan\_Floor](https://discourse.mcneel.com/u/Jurriaan_Floor)\
**Replies:** 1\
**Last updated:** [June 10, 2023, 8:38am UTC](https://discourse.mcneel.com/t/feature-request-add-user-data-as-input-for-all-karamba-components/161220 "2023-06-10T08:38:39Z")

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Hi @karamba3d Can UserString, UserValue and UserObject be made available, if applicable, as optional input to all the Karamba components? For our intended workflow this would be really convenient. @user1271 and I conclu…

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## [How to add my custom document/object user data to File3dm?](https://discourse.mcneel.com/t/how-to-add-my-custom-document-object-user-data-to-file3dm/133924)

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**Author:** [@jamie.lin](https://discourse.mcneel.com/u/jamie.lin)\
**Replies:** 2\
**Last updated:** [November 30, 2021, 5:02am UTC](https://discourse.mcneel.com/t/how-to-add-my-custom-document-object-user-data-to-file3dm/133924 "2021-11-30T05:02:50Z")

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I have both document user data and object user data in my plugin. To keep from data breach, I will not save a 3dm file on local machine. I keep those data in my document(RhinoDoc) by assign them into File3dm class and …

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## [ObjRef not working after being read from UserData](https://discourse.mcneel.com/t/objref-not-working-after-being-read-from-userdata/130494)

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**Author:** [@heine.kristensen](https://discourse.mcneel.com/u/heine.kristensen)\
**Replies:** 1\
**Last updated:** [September 21, 2021, 5:08pm UTC](https://discourse.mcneel.com/t/objref-not-working-after-being-read-from-userdata/130494 "2021-09-21T17:08:01Z")

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Hi, I have an object with read and write functions on, which I attach to objects as userdata. It contains some ObjRef and ObjRef array which seems to be written/saved just fine, but when reloading/opening the project i…

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## [Updating userdata information after object has been moved](https://discourse.mcneel.com/t/updating-userdata-information-after-object-has-been-moved/114868)

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**Author:** [@mattipi](https://discourse.mcneel.com/u/mattipi)\
**Replies:** 1\
**Last updated:** [December 30, 2020, 12:24am UTC](https://discourse.mcneel.com/t/updating-userdata-information-after-object-has-been-moved/114868 "2020-12-30T00:24:13Z")

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Hi @dale and everyone else. I am creating a BIM type program on top of rhino. For that I have classes like node line and member which I would like to relate to rhino geometry object like point and line. As an example I …

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## [CustomGrips and UserData behaviour on transformation](https://discourse.mcneel.com/t/customgrips-and-userdata-behaviour-on-transformation/95928)

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**Author:** [@rgr](https://discourse.mcneel.com/u/rgr)\
**Replies:** 3\
**Last updated:** [July 15, 2020, 10:22am UTC](https://discourse.mcneel.com/t/customgrips-and-userdata-behaviour-on-transformation/95928 "2020-07-15T10:22:16Z")

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Hello, I have a custom UserData class which is attatched to a block. Inside the UserData, there is a polyline (“BaseLine” in my code) which provides custom grips on all of its points, on which I then can modify the bloc…