JavaScript | Convert Array to JSON Object

Learn how to convert an array to JSON in JavaScript in this step-by-step tutorial. We will cover the different ways to convert an array to JSON, including using the built-in JSON.stringify() method. This tutorial is perfect for beginners who want to learn how to work with arrays and JSON in JavaScript.

What is JSON?

JSON means JavaScript Object Notation. JSON is an extremely lightweight data-interchange format for data exchange between server-side and client side which is quick and easy to parse and generate.

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1. Convert Array to JSON Object JavaScript

You can use JSON.stringify to convert an array into a JSON formatted string in JavaScript.

Suppose there is an array such as “[6, 7, 8, 9]”. If you want to convert this array to JSON Object in javascript. Let’s see the example below

Ex:

    var arr = [5, 6, 7, 8]; 
    var arrayToString = JSON.stringify(Object.assign({}, arr));  // convert array to string
    var stringToJsonObject = JSON.parse(arrayToString);  // convert string to json object
    
    console.log(stringToJsonObject);

Output :

  {
       "0": 5,
       "1": 6,
       "2": 7,
       "2": 8
   }

Here,

• 1.JSON.stringify() and Object.assign() method convert array to JSON string.
• 2.JSON.parse() method convert string to JSON object in javascript.

2. Converting an Object to an Array

When converting an object to an array, we’ll use the .entries() method from the Object class. This will convert our object to an array of arrays. Each nested array is a two-value list where the first item is the key and the second item is the value.

Ex:

const obj = {"1":5,"2":7,"3":0,"4":0,"5":0,"6":0,"7":0,"8":0,"9":0,"10":0,"11":0,"12":0};
console.log(Object.entries(obj));

3. Convert two dimensional ( 2d ) arrays to JSON Object JavaScript

Suppose there is an array such as

var arr = [
    ["Status", "Name", "Marks", "Position"], 
    ["active", "Akash", 10.0, "Web Developer"],
    ["active", "Vikash", 10.0, "Front-end-dev"],
    ["deactive", "Manish", 10.0, "designer"],
    ["active", "Kapil", 10.0, "JavaScript developer"],
    ["active", "Manoj", 10.0, "Angular developer"],
];

If you want to convert this array to JSON Object in javascript. Let’s see the example below :

Ex:

//array.
var arr = [
    ["Status", "Name", "Marks", "Position"], 
    ["active", "Akash", 10.0, "Web Developer"],
    ["active", "Vikash", 10.0, "Front-end-dev"],
    ["deactive", "Manish", 10.0, "designer"],
    ["active", "Kapil", 10.0, "JavaScript developer"],
    ["active", "Manoj", 10.0, "Angular developer"],
];
 
//javascript create JSON object from two dimensional Array
function arrayToJSONObject (arr){
    //header
    var keys = arr[0];
 
    //vacate keys from main array
    var newArr = arr.slice(1, arr.length);
 
    var formatted = [],
    data = newArr,
    cols = keys,
    l = cols.length;
    for (var i=0; i<data.length; i++) {
            var d = data[i],
                    o = {};
            for (var j=0; j<l; j++)
                    o[cols[j]] = d[j];
            formatted.push(o);
    }
    return formatted;
}

#javascript #Array #json