Insert Javascript (jquery) variable in a JSON string

Question

I promise having searched a "simple answer to this" (I insist on the word "Simple"), but unfortunatly I cant find any answer (or approachable answer regarding my understanding of JSON/Jquery). Surely I'm too noob in JSON to create a precise question (and find the right answer...)

Anyway, here my problem.

My JSON file prices.json (example) :

{
  "test1" : {
    "sub_test1_1" : 10,
    "sub_test1_2" : 20,
    "sub_test1_3" : 30,
  },
  "test2" : {
    "sub_test2_1" : 40,
    "sub_test2_2" : 50,
    "sub_test2_3" : 60,
  }
}

Here my jquery

$("#testing").click(function() {
  $.getJSON('/prices.json', function(jsonData) {
    alert(jsonData.test2.sub_test_2_2);
  });
});

The alert give me the right data : 50

So now, I define a simple variable like

var crazyVar = test2;

And I want to put this variable in the string "jsonData.test2.sub_test_2_2" like

$("#testing").click(function() {
  $.getJSON('/prices.json', function(jsonData) {
    alert(jsonData.crazyVar.sub_test_2_2);
  });
});

Of course, it fail :(

I read that I need to play with object, I tried all way to transform crazyVar in a sort of "Object" but impossible to find a just simple solution.

crazyVar is not assigned a value test2 will be null should it be jsonData.test2 ? — fuzzybear, Jan 02 '18 at 17:26
`jsonData.test2.sub_test_2_2 = crazyVar;` before alerting `alert(jsonData.test2.sub_test_2_2)` — connexo, Jan 02 '18 at 17:26
The ```test2``` variable is ```undefined``` when you assign ```crazyVar```. You want something like this: jsonData.crazyVar = {}; jsonData.crazyVar.sub_test_2_2 = 70; — 4thex, Jan 02 '18 at 17:31

brk · Answer 1 · 2018-01-02T17:30:45.503

5

While accessing a object key using variable use square [] brackets

var crazyVar = 'test2';
jsonData[crazyVar].sub_test_2_2

edited Jan 02 '18 at 17:30

answered Jan 02 '18 at 17:26

brk

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Work like a charm, but if I want to extend like var crazyVar_1 = 'test2'; var crazyVar_2 = 'sub_test_2_2'; Can I use ? : jsonData[crazyVar_1].jsonData[crazyVar_2] (don't work actualy) – s.artexess Jan 02 '18 at 18:46

Insert Javascript (jquery) variable in a JSON string

1 Answers1