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I recently stumbled upon this issue while debugging an application that didn't handle JSON payload as expected.
As it turns out, Unflatten From JSON breaks on NUL characters, even though Flatten To JSON properly encodes them as ("\u0000").


I have confirmed the behavior in LabVIEW 2017, 2019, and 2020 (all with latest service packs and patches), currently waiting for confirmation by NI.
Workaround: Use JSONtext

Package for working with JSON.  Uses high-speed text parsing, rather than building an intermediate representation as with prior LabVIEW JSON libraries (this is much faster).  Allows easy working with "subitems" in JSON format, or one can convert to/from LabVIEW types.  Uses the new "malleable VIs" of LabVIEW 2017 to convert to any LabVIEW type directly.
JSON text makes use of a form a JSON Path notation, allowing easy and rapid access to the subitems of interest.
Requires LabVIEW 2017 and install by VIPM 2017 or later.
Original conversation about JSONtext.
On the LabVIEW Tools Network.
JDP Science Tools group on NI.com.
Copyright 2017 JDP Science Limited

View File JSON LabVIEW
JSON is a data interchange format (sometimes compared to XML, but simpler). There are multiple projects to create a JSON package for LabVIEW. This is yet another one motivated by this hijacked conversation originally about a different project to convert JSON into LabVIEW Variants.

This project uses a set of LVOOP classes to match the recursive structure of JSON, rather than variants. It allows conversation to and from JSON. All functionality is available through two polymorphic VIs: Set and Get. In addition to Get and Set VIs for common data types, one can also convert directly to or from complex clusters via variant-JSON tools.

Copyright 2012-2016 James David Powell, Shaun Rumbell, Ton Plomp and James McNally.
[Note: if you are using LabVIEW 2017, please also see the JSONtext library as a an alternative.]
Submitter drjdpowell Submitted 10/04/2012 Category General LabVIEW Version  

Hi,
I'm receiving a JSON string from a web API, which I'm trying to convert into a cluster (of clusters) but I've run into some problems:
1) Sometimes the order of the elements in the JSON string changes, which causes my conversion to fail.
2) Sometimes the "object" returned via JSON is null, which causes my conversion to fail if I use clusters within clusters. It works with variants in clusters but then I need to convert the all the variants manually
Is there any way to improve my code to fix those problems? The attached snippet is a simplified version. In my project, the first JSON string to data is done in a library. The second conversion from "result" variant to data is done in my application. This makes a direct conversion from JSON string more difficult.

JSON is a data interchange format (sometimes compared to XML, but simpler). There are multiple projects to create a JSON package for LabVIEW. This is yet another one motivated by this hijacked conversation originally about a different project to convert JSON into LabVIEW Variants.

This project uses a set of LVOOP classes to match the recursive structure of JSON, rather than variants. It allows conversation to and from JSON. All functionality is available through two polymorphic VIs: Set and Get. In addition to Get and Set VIs for common data types, one can also convert directly to or from complex clusters via variant-JSON tools.

Copyright 2012-2016 James David Powell, Shaun Rumbell, Ton Plomp and James McNally.
[Note: if you are using LabVIEW 2017, please also see the JSONtext library as a an alternative.]