Logic App - Expression to get a particular substring from a string

Question

I have below JSON input in my Logic App:

{
   "d":{
      "results":[
         {
            "userId":"123",
            "payGrade":"KF15-314-370-AGR342-PD1"
         },
         {
            "userId":"456",
            "payGrade":"KF14-269-313-AGR291-R4"
         },
         {
            "userId":"789",
            "payGrade":"KF14-269-313-AGR289"
         }
      ]
   }
}

I want to use only a last part/substring after "AGR-" from "payGrade" (i.e. "PD1" from "KF15-314-370-AGR342-PD1" | "R4" from "KF14-269-313-AGR291-R4" | and if there's nothing after "AGR" just make it blank)

I've been looking at "substring('text', startIndex, length)" expression function but it only returns substring from a particular position/index so not sure how to achieve this.

Answer 1

There are two ways of doing this,

Short way (I do not recommend this, as the code itself is nested, make sure there is a loop on results array)

if(equals(length(split(items('For_each')?['payGrade'],'-')),5), last(split(items('For_each')?['payGrade'],'-')),'')

Long answer (Recommended, it is much concise and easy to follow)

You can follow the logic in the image below

1. Make an empty array variable (Used to return, since u are looping in array and can't really return any result from it, modify as needed)

2. Loop through the results array

3. Split the string using "-" @{split(items('For_each')?['payGrade'],'-')}

4. Condition to check whether the result from split is 4 or 5 item

You should get 5 items if there is payGrade, and 4 if there is no payGrade

5. Take the value accordingly and append it to the variable on the outer scope

6. Do whatever you want with that Variable.