Javascript: Parse JSON output result

Question

How can i retrieve the values from such JSON response with javascript, I tried normal JSON parsing seem doesn't work

[["102",true,{"username":"someone"}]]

Tried such codes below:

url: "http://somewebsite.com/api.php?v=json&i=[[102]]",
onComplete: function (response) {
var data = response.json[0];
console.log("User: " + data.username); // doesnt work

Answer 1

var str = '[["102",true,{"username":"someone"}]]';
var data = JSON.parse(str);
console.log("User: " + data[0][2].username);

1. Surround someone with double quotes
2. Traverse the array-of-array before attempting to acces the username property

If you are using AJAX to obtain the data, @Alex Puchkov's answer says it best.

Answer 2

So the problem with this is that it looks like an array in an array. So to access an element you would do something like this.

console.log(obj[0][0]);  

should print 102

Lets say you created the object like so:

var obj = [["102",true,{"username":someone}]];  

this is how you would access each element:

obj[0][0] is 102

obj[0][1] is true
and obj[0][2]["username"] is whatever someone is defined as

From other peoples answers it seems like some of the problem you may be having is parsing a JSON string. The standard way to do that is use JSON.parse, keep in mind this is only needed if the data is a string. This is how it should be done.

var obj = JSON.parse(" [ [ "102", true, { "username" : someone } ] ] ")

Answer 3

It depends on where you are getting JSON from:

If you use jQuery

then jQuery will parse JSON itself and send you a JavaScript variable to callback function. Make sure you provide correct dataType in $.ajax call or use helper method like $.getJSON()

If you getting JSON data via plain AJAX

then you can do:

var jsonVar = JSON.parse(xhReq.responseText);