UCCX Script String Substring Function

Question

I cannot use the Substring function to obtain a specific value from a string variable.
My substring position is variable, so I need to put a variable, loop and increment it the position.
When I try to add the below command, this is getting the error message:
Command: set STR_Resultado = STR_Valor.substring(P1,2+1)
Error message:
"Unable to parse expression; error while parsing string: STR_Valor.substring(P1,P2); nested exception is java.lang.NullPointerException"

Answer 1

To ask the obvious: do either P1 or STR_Valor have a null value at the time that step executes? If they do, this is the expected result. Use an On Exception Goto step or other preventative code to protect the step from this exception.
Why does your command and the error not match?
Command: substring(P1,2+1)
Exception: substring(P1,P2)
If the command statement is what you're actually using (your image attachment isn't showing) then I believe you have a syntax error. The substring method documentation doesn't suggest you can do additive operations here.
Most likely the first bullet though...
PS- You may want to get the length of the string first and ensure that the startIndex and endIndex are less than or equal to it. I believe you'll get a IndexOutOfBoundsException if you try to pull a substring from outside the bounds of the actual string.
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