# Struggling with dynamic tags in expressions

**URL:** <https://forum.inductiveautomation.com/t/struggling-with-dynamic-tags-in-expressions/85730>\
**Category:** Ignition\
**Tags:** ignition81, perspective\
**Created:** [February 14, 2024, 11:43pm UTC](https://forum.inductiveautomation.com/t/struggling-with-dynamic-tags-in-expressions/85730 "2024-02-14T23:43:19Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![ian.sebryk](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/ian.sebryk/32/49319_2.png) [@ian.sebryk](https://forum.inductiveautomation.com/u/ian.sebryk)\
**Post date:** [February 14, 2024, 11:43pm UTC](https://forum.inductiveautomation.com/t/struggling-with-dynamic-tags-in-expressions/85730/1 "2024-02-14T23:43:19Z")

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when i directly access the tag path, i get the value as expected (`curr_mA`). but when i try to make it dynamic, it just get `null`. can someone tell me what i'm doing wrong?

 ![Screenshot 2024-02-14 164046](https://us1.discourse-cdn.com/inductiveautomation/original/3X/6/6/66c3eb79b0ff256d517318f3a3a42bff22b2e869.png)

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**Author:** ![lrose](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/lrose/32/62724_2.png) [@lrose](https://forum.inductiveautomation.com/u/lrose)\
**Post date:** [February 14, 2024, 11:54pm UTC](https://forum.inductiveautomation.com/t/struggling-with-dynamic-tags-in-expressions/85730/2 "2024-02-14T23:54:23Z")

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I would create custom properties with an indirect tag binding, rather than the `tag()` expression.

And then you can reference those properties in your expression structure if need be.

The problem with this:

```auto
tag("[]Assets/....")

```

Is that it is an invalid tag path. You have provided no TagProvider. If you want to use a default tag provider then you need to proved that TagProviders name, in this context (relative tag paths are invalid here).

So something like `tag("[default]Assest/....")`.

I can't say what the issue is with `isActive` because I don't know what the value of `thatSettingOnThatSettingsPage` is.

Seriously though - [Tag Bindings in Perspective - Ignition User Manual 8.1 - Ignition Documentation](https://docs.inductiveautomation.com/display/DOC81/Tag+Bindings+in+Perspective)  
(Scroll down to Indirect Binding Mode)

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**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:** [February 14, 2024, 11:57pm UTC](https://forum.inductiveautomation.com/t/struggling-with-dynamic-tags-in-expressions/85730/3 "2024-02-14T23:57:22Z")

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> [@lrose](#):
>
> indirect tag binding, rather than the `tag()` expression

Let me emphasize this. If you are using the `tag()` expression function in a user interface binding, you are screwing up.

You can find many rants here under my name on this topic.

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**Author:** ![nminchin](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/nminchin/32/6911_2.png) [@nminchin](https://forum.inductiveautomation.com/u/nminchin)\
**Post date:** [February 15, 2024, 12:15am UTC](https://forum.inductiveautomation.com/t/struggling-with-dynamic-tags-in-expressions/85730/4 "2024-02-15T00:15:08Z")

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> [@lrose](#):
>
> I would create custom properties with an indirect tag binding, rather than the `tag()` expression.

> [@pturmel](#):
>
> Let me emphasize this. If you are using the `tag()` expression function in a user interface binding, you are screwing up.

"Thirding" this to drive it home!

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<div class="post-metadata">

**Author:** ![ian.sebryk](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/ian.sebryk/32/49319_2.png) [@ian.sebryk](https://forum.inductiveautomation.com/u/ian.sebryk)\
**Post date:** [February 15, 2024, 12:57am UTC](https://forum.inductiveautomation.com/t/struggling-with-dynamic-tags-in-expressions/85730/5 "2024-02-15T00:57:10Z")

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> [@lrose](#):
>
> what the issue is with `isActive`

placeholder. not germaine.

okay. i read (a lot) and i will create a custom property instead. thanks for the helpful pointer. i recall @pturmel saying something to this effect in another post, but i couldn't find it (fast enough). 😛