access value of an array through the name in the Expression in Power Automate/ MS flow

Question

I have created an empty list and appending to it in the flow, at the end, I need to get the value of a specific key through an Expression, Is this possible? and if yes, how?

Please see the below screenshots.

Initialise:

Append:

I am appending data to this array in a Do while loop, the content of each run (total 2 run) is shown below:

First Run:

Second Run:

And the output of Compose"

[
  {
    "name": "Fy2020",
    "value": 2.5
  },
  {
    "name": "Fy2021",
    "value": 2.5
  } 
]

Retrieve and assign it to another variable:

I have tried different approaches and got different errors:

variables('FYearsValues')?['value']?[0] erorr:

 'The template language expression 'variables('FYearsValues')?['value']?[0]' cannot be evaluated 
     because property 'value' cannot be selected. Array elements can only be selected using an 
   integer index. Please see https://aka.ms/logicexpressions for usage details.'.

variables('FYearsValues')?['Value']?[0] Error:

The template language expression 'variables('FYearsValues')?['Value']?[0]' cannot be
  evaluated because property 'Value' cannot be selected. Array elements can only be selected using an
  integer index. Please see https://aka.ms/logicexpressions for usage details.'.

variables('FYearsValues')[0] Error:

The variable 'FYCounter_' of type 'Integer' cannot be initialized or updated with value '{
 "name": "Fy2020",
 "value": 2.5
 }' of type 'Object'. The variable 'FYCounter_' only supports values of types 'Integer'.

and for this: variables('FYearsValues')['Fy2020'] Error:

Unable to process template language expressions in action 'Set_variable_3' inputs at line '1' and 
column '2857': 'The template language expression 'variables('FYearsValues')['Fy2020']' cannot be 
 evaluated because property 'Fy2020' cannot be selected. Array elements can only be selected using an 
integer index. Please see https://aka.ms/logicexpressions for usage details.'.  

The best formula for me would be something like this

variables('FYearsValues')['Fy2020'] which needs to return 2.5 (i.e.value)

but I can work with indexes too (e.g. variables('FYearsValues')[0] which needs to return 2.5 (i.e.value)

Answer 1

If it's an array, you would access it with index starting at 0 like

 variables('MyArray')?[1]

Index can be a variable as well, in that case it would be like

variables('MyArray')?[variables('varIndex')]

However, if it's a JSON object collection, then first need to find the item by the index and then find the items' value by property name. In the example below, [results] is a collection of items, but retrieving user email by property

body('Parse_JSON')?['d']?['results'][1]['User']['Email']