trouble Accessing JSON structure using variables, help

sdetweil

I am trying to access a json structure using variables containing the parts of the structure.

according to the javascript and json docs, when u want to use variables, u must use the bracket notation

so

object[key1][key2].value

when object looks like this

{
  "fred":{"mary":"value1","sue":value2"}
}

so

var a='fred'
var b='sue'

and

object[a][b].value should return 'value2'

but in my module, I am getting cannot access 'sue' of undefined
if I make a variable then it works, but still throws an error

var bob=object[a][b] returns error cannot access 'sue' of undefined

but if I do
var bob= object[a.toString()][b.toString()]

then it works, and bob= the sue data item and
bob.value works… BUT still throws an error cannot access value of undefined… but it worked (I debug step thru the code)…

if I use literals instead of variables as the key names, then it works… but I need to use variables to reduce the code by using a loop to walk thru the big json object…

do we have some downlevel javascript? or??

this should be SO easy, but something is weird…

sdetweil

@sdetweil well, its a side effect of the way the code works…

if (object[key][key] !==‘undefined’)

will throw an access error if either of the two keys are not in the object… BEFORE you can check the results with the if…

SO, wrap with try/catch and all is well…

Mykle1

@sdetweil

You genius types are awesome!

Create the topic. Reply to yourself. Mark topic solved (by self).

sdetweil

@mykle1 there is no better thought motivator than posting on a live forum…!!