# How to reference UDT Properties like Parameters in Gateway Event Tag Change Scripts

**URL:** <https://forum.inductiveautomation.com/t/how-to-reference-udt-properties-like-parameters-in-gateway-event-tag-change-scripts/89004>\
**Category:** Ignition\
**Created:** [April 17, 2024, 8:36pm UTC](https://forum.inductiveautomation.com/t/how-to-reference-udt-properties-like-parameters-in-gateway-event-tag-change-scripts/89004 "2024-04-17T20:36:59Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![framebuilder](https://avatars.discourse-cdn.com/v4/letter/f/96bed5/32.png) [@framebuilder](https://forum.inductiveautomation.com/u/framebuilder)\
**Post date:** [April 17, 2024, 8:36pm UTC](https://forum.inductiveautomation.com/t/how-to-reference-udt-properties-like-parameters-in-gateway-event-tag-change-scripts/89004/1 "2024-04-17T20:36:59Z")

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We know how to reference UDT Properties like parameters in Tag Event Scripts like this:  
paramValue = tag['parameters']['myParam']

But is there a way to reference them in Gateway Event Tag Change Scripts? I've seen people recommending to create an Expression Tag in the UDT that references the parameter and then just read that Expression tag in the script. Seems clunky to me. Are there any other ways?

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<div class="post-metadata">

**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [April 17, 2024, 9:50pm UTC](https://forum.inductiveautomation.com/t/how-to-reference-udt-properties-like-parameters-in-gateway-event-tag-change-scripts/89004/2 "2024-04-17T21:50:40Z")

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Construct the appropriate paths and use `system.tag.readBlocking()`. Preferably one call to get everything you need.

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<div class="post-metadata">

**Author:** ![framebuilder](https://avatars.discourse-cdn.com/v4/letter/f/96bed5/32.png) [@framebuilder](https://forum.inductiveautomation.com/u/framebuilder)\
**Post date:** [April 18, 2024, 2:14pm UTC](https://forum.inductiveautomation.com/t/how-to-reference-udt-properties-like-parameters-in-gateway-event-tag-change-scripts/89004/3 "2024-04-18T14:14:36Z")

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Looks like you can append /Parameters in the UDT tagPath

```auto
tagPath = "[default]temp/udt1/Parameters.myParam"
param = system.tag.readBlocking(tagPath)[0].getValue()

```

We can't find any documentation showing this but maybe we're looking in the wrong places. Does anyone see any issue with this approach or is there a better way perhaps?

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<div class="post-metadata">

**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [May 23, 2026, 8:02pm UTC](https://forum.inductiveautomation.com/t/how-to-reference-udt-properties-like-parameters-in-gateway-event-tag-change-scripts/89004/4 "2026-05-23T20:02:19Z")

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A post was merged into an existing topic: [Gatway tag change script, getting id from db best practice](https://forum.inductiveautomation.com/t/gatway-tag-change-script-getting-id-from-db-best-practice/115677/6)