This will convert it into an array (which is the JSON representation you specified):

var array = myString.split(',');

If you need the string version:

var string = JSON.stringify(array);

Simple:

var data = [{"name":"Marine Lines","location_id":3},{"name":"Ghatkopar","location_id":2}]
var result = data.map(function(val) {
  return val.location_id;
}).join(',');

console.log(result)

I assume you wanted a string, hence the .join(','), if you want an array simply remove that part.

var json = [];
var to = '[email protected],[email protected],[email protected]';
var toSplit = to.split(",");
for (var i = 0; i < toSplit.length; i++) {
    json.push({"email":toSplit[i]});
}

const array = str.split(',');

MDN reference, mostly helpful for the possibly unexpected behavior of the limit parameter. (Hint: "a,b,c".split(",", 2) comes out to ["a", "b"], not ["a", "b,c"].)

You can do the following,

data = [
  {'id': 1,
  'name': 'book',
  'colors': 'red, yellow, blue'
  },
  {'id': 2,
  'name': 'book',
  'colors': 'red, yellow, blue'
  }
 ];
 
 ret = data.map((item) => {
   return {...item, colors: item.colors.split(',').map(item => item.trim())};
 })

console.log(ret);

var jsonfied = {
    names: names.replace( /,$/, "" ).split(",").map(function(name) {
        return {name: name};
    })
};

result of stringfying jsonfied:

JSON.stringify( jsonfied );

{
    "names": [{
        "name": "Mark"
    }, {
        "name": "Matthew"
    }, {
        "name": "Luke"
    }, {
        "name": "John"
    }]
}

Live DEMO

This can be achieved via the join() method which is built into the Array type:

const object = {
"id" : "122223232244",
"title" : "התרעת פיקוד העורף",
"data" : ["עוטף עזה 218","עוטף עזה 217"]
}

/* Join elements of data array in object to a comma separated string */
const value = object.data.join();

console.log(value);

If no separator argument is supplied, then the join() method will default to use a comma separator by default.

Update

If the JSON was supplied in raw text via a string you can use the JSON.parse() method to extract an object from the JSON string value as a first step like so:

const json = `{"id" : "122223232244","title" : "התרעת פיקוד העורף","data" : ["עוטף עזה 218","עוטף עזה 217"]}`

/* Parse input JSON string */
const object = JSON.parse(json);

/* Join elements of data array in object to a comma separated string */
const value = object.data.join();

console.log(value);

Try:

var initialString = "'California',51.2154,-95.2135464,'data'";
var dataArray = initialString .split(",");

You need to parse the string you get from the sessionStorage, then you can map and join:

var profile = '{"domiciles":[{"country":"AF"},{"country":"AX"},{"country":"AL"}],"investor":[{"type":"ii"},{"type":"pi"}]}'; // sessionStorage.getItem("profile");

var dataResidence = JSON.parse(profile);

function mapAndJoin(arr, key) {
  return arr.map(function(o) {
    return o[key];
  }).join();
}

var domiciles = mapAndJoin(dataResidence.domiciles, 'country');

var investor = mapAndJoin(dataResidence.investor, 'type');

console.log(domiciles);

console.log(investor);

Push each value into an array and then use .join() to make a comma-delimited string.

const response = {
  chartstatus: [{
      abs_status: "Bekerja",
      total: "12"
    },
    {
      abs_status: "Tanpa Keterangan",
      total: "5"
    },
    {
      abs_status: "Hari Libur",
      total: "1"
    }
  ]
}

let nama_status = [];
let jumlah = [];

$.each(response.chartstatus, function(key, value) {
  status = value.abs_status.toString();
  nama_status.push('"' + status + '"');
  jumlah.push(value.total)

});
console.log(nama_status.join(', ')); 
console.log(jumlah.join(', '));

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