Day: January 2, 2019

NotesJsonNavigator.getElementByPointer example

Sample code:

Const white = |{"color": "white", "category": "value","code": {"rgba": [0,0,0,1],"hex": "#FFF"}}|

Public Sub testJsonNavGetElementByPointer()
	Dim session As New NotesSession
	Dim jsnav As NotesJSONNavigator 
	Dim el As NOTESJSONELEMENT
	
	Set jsnav = session.CreateJSONNavigator(removeCRLF(white)) 
	
	'// returns "value"
	Set el = jsnav.Getelementbypointer("/category")
	MsgBox "category: " + el.Value
	
	'// returns "#FFF"
	Set el = jsnav.Getelementbypointer("/code/hex")
	MsgBox "hex: " + el.Value
	
	'// returns the 4th element in the rgba array  "1"
	Set el = jsnav.Getelementbypointer("/code/rgba/3")
	MsgBox "code/rgba/3: " + el.Value
End Sub

General information about JSON pointer: https://tools.ietf.org/html/rfc6901


NotesJsonNavigator.getNthElement does not obey boundries

I stumbled upon an issue with NotesJsonNavigator getNthElement(index) method.

It looks like there is no boundry check, which leads to some inconsitent behaviour and unpredictable results.

Here is the code that I used in my test.

%REM
	Sub testJsonNavGetNthElement
%END REM
Public Sub testJsonNavGetNthElement
	Dim s As New NotesSession 
	Dim jsnav As NotesJSONNavigator
	Dim el As NotesJSONElement
	
	Set jsnav = s.CreateJSONNavigator(|{ "element1" : "value 1", "element2" : "value 2", "element3 ": "value 3" }|)	
	
	Set el = jsnav.GetNthElement(0)
	Stop
	Set el = jsnav.GetNthElement(1)
	Stop
	Set el = jsnav.GetNthElement(2)
	Stop
	Set el = jsnav.GetNthElement(3)
	Stop
	Set el = jsnav.GetNthElement(1000)
	Stop
End Sub

The issue occurs with index < 1 and > upper bound of the array.

Index 0 AND index 1 both return the same value; “value 1“.
Index 1000 returns NULL or nothing.

This is not the expected behaviour. At least I would expect some “out of bounds” error.
Also, it is not clear for me what the base for the index is. Do we start counting at 0 or do we start with 1 ?

According to the documentation, the index is 1-based.