Since array literal notation is still valid JSON, you can use JSON.parse() to convert that string into an array, and from there, use it's values.

Use with AIvar test = "[1,2]";
parsedTest = JSON.parse(test); //an array [1,2]

//access like and array
console.log(parsedTest[0]); //1
console.log(parsedTest[1]); //2

No need of jquery. Just use .split() function to achieve this.

let string = 'Chemistry,English,History';
let arr = string.split(',');
console.log(arr)

You must replace all your "'" to "\"" Then you can use JSON.parse() for convert your string into an array. Just like this:

var answer = "['2012-2','2012-3','2012-4','2013-1','2013-2','2013-3','2013-4','2014-1']";
answer = answer.split("'").join("\"");

var arrPeriods = JSON.parse(answer);

var tr = $('<tr><td>Title</td></tr>');

$.each(arrPeriods, function(index, value) {
  tr.append('<td>' + value + '</td>');
});

$('table').append(tr);

Since new Date(2015,9,25) is not valid JSON, than you need to use eval(yourString) to parse your string to valid Object:

console.log(eval('[{ date: new Date(2015,9,25), NAV: 12},{ date: new Date(2016,9,25), NAV: 22}]'));

I think that the best way of doing this, as Douglas Crockford (one of the biggests gurus of JavaScript) suggests in here is using the JSON native parser, as it is not only faster than the eval(), it's also more secure.

Native JSON parser is already available in:

• Firefox 3.5+
• IE 8+
• Opera 10.5+
• Safari Safari 4.0.3+
• Chrome (don't know which version)

And Crockford has made a safe fallback in javascript, called json2.js, which is an adaption of the eval() approach, with some security bits added and with the native JSON parsers API. You just need to include that file, remove its first line, and use the native JSON parser, and if it's not present json2 would do the work.

Here is an example:

var myJSONString = '{ "a": 1, "b": 2 }',
    myObject = JSON.parse(myJSONString);

Once parsed you'll get an object with attributes a and b, and as you may know, you can treat an object as a hash table or associative array in JavaScript, so you would be able to access the values like this:

myObject['a'];

If you just want a simple array and not an associative one you could do something like:

var myArray = [];
for(var i in myObject) {
    myArray.push(myObject[i]);
}

Lastly, although not necessary in plain JavaScript, the JSON spec requires double quoting the key of the members. So the navite parser won't work without it. If I were you I would add it, but if it is not possible use the var myObject = eval( "(" + myString + ")" ); approach.

I have something like this: [['1', 'client1'], ['2', 'client2'], ['3', 'client3']] and would like to get: 1 - client1.....

The .value should be valid JSON or RegExp or String methods need to be used to convert invalid JSON to valid JSON. Note the single quotes at HTML attribute surrounding the value and double quotes within the value of the attribute

[["1", "client1"], ["2", "client2"], ["3", "client3"]]

You can then use JSON.parse() to convert JSON string to JavaScript object and use for..of loop to iterate each element of each nested array.

let value = JSON.parse(clients.value);

for (let [a, b] of value) {
  console.log(a, b)
}

<input id="clients" value='[["1", "client1"], ["2", "client2"], ["3", "client3"]]'>

var arr = "abcdef".split(''); // creates an array from a string

var str = arr.join(''); // creates a string from that above array

var obj = $.parseJSON('[["1","aaaaaa","1"],["2","bbbbbbb","2"],["3","ccccccc","3"]]')

Assuming jquery is ok to use because of tag.

You could write a basic parser.

function nextC(i, text) {
  if (i < text.length)
    return text.charAt(i);
  return "";
}

function skipSpace(i, text) {
  while (c == " ")
    c = nextC(++i, text);
  return i;
}  

function parseObj(text) {
  var lablel = "";
  var value = "";
  var obj = {};
  for (var i = 0; i < text.length; i++) {
    var c = text.charAt(i);
    if (c == "[") {
      while (c != "]") {
        c = nextC(++i, text);
        label += c;
      }
    } else if (c == " ") {
      i = skipSpace(i, text);
      c = nextC(i, text);
      if (c == "=") {
        c = nextC(++i, text);
        if (c == ">" {
          i = skipSpace(i, text);
          c = nextC(i, text);
          while (c != "\n") {
            c = nextC(++i, text);
            value += c;  
          }          
          obj[label] = value;
        }
      }
    }
  }
  return obj;
}
var text = $("span").text();
var obj = parseObj(text);
alert(obj["namePerson/first"]);

Note This may be prone to bugs. If you are trying to transfer data from server to client, try using JSON or XML.

To parse it you need to use double quotes instead of single.

This should work:

services = '["service1", "service2", "service3"]'
JSON.parse(services)