I am now doing it by opening the JSON file using the file IO VIs, reading the full file to a string and then using string manipulations like match regular expression an search and replace string.
I then replace the whole file with the manipulated string.
This is now working, but I thought it is long winded way. I went for this way of doing it because I am not familiar with Native JKI JSON VIs.
Can some kind soul over there show me how it is done with native JSON VIs.
Attached is the program that shows how I am doing it.
Solved! Go to Solution.
Note: there are multiple JSON tools available. The native ones that come with LabVIEW are different that the JKI library you are using. Personally, I use and recommend JSONtext, a library I wrote. Definitely use a real JSON library, not string parsing, as there are all sorts of potential bugs you could run into.
Thanks very much for your help, I have tried you application and it does what is says in the tin.