How to convert a string into a Value in a Expression function?

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1

I think it is a simple question but I would like to know how I could show the value of that specific tag?

for now I get it by means of a custom property of another window but I need by means of an expression to change that string to the value of that tag in particular.

I tried with tag(concat({Root Container.tagPath} , "/GSC_Racks/Rack_Global_3/Word/Rack_Run_State"))

is there any other alternative or suggestion?

thank you very much

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To read an indirect tag path (eg a parameterised tag path), you should be using an indirect tag binding.
For example:

Indirect path:
{1}/GSC_Racks/Rack_Global_3/Word/Rack_Run_State

And link 1 to your root container tagpath

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3

Can you be a little more specific please? I have never used the Indirect Tag method.

4

An indirect tag binding is basically a parameterized path. You put in place holders (that look like this: {some_identifier}) in the path, and give them values dynamically.

For exemple, in your case, the constant part of the path is /GSC_Racks/Rack_Global_3/Word/Rack_Run_State, and it takes a variable part before that.
So, you make an indirect tag binding and use a path like this:
{prefix}/GSC_Racks/Rack_Global_3/Word/Rack_Run_State
In the parameters list below the path, you now have one called prefix, and you can give it a value. Make this value a binding to {Root container.tagPath}, and you're done.

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5

It'll look something like this:

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You can build your path exactly as @pascal.fragnoud described.
You can also take a look at the page on the manual for indirect tag bindings here:
https://docs.inductiveautomation.com/display/DOC81/Indirect+Tag+Bindings+in+Vision
And i would recommend you to take the Inductive University's free credential course, but this video should be enough for this topic:

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6

thank you very much, I have seen the videos and documentation about the indirec tags and I have found the solution!

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