JSON Objects: JavaScript Object Notation (JSON) is a text-based, human-readable interchange format used for representing simple data structures and objects in web browser-based code. JavaScript objects can only exist within the JavaScript language, so when you are working with data that needs to be accessed by various languages, it is best to refer to JSON.

Rules to declare an object:

  • The object is always defined inside the curly brackets { }.
  • Objects are written in key pairs.
  • The keys must be strings, and their values must be a valid JSON data type. The JSON data types can be number, string, object, boolean, array, or null.
  • The keys and values are separated by a colon(“:”).
  • Each key or value pair is separated by a comma.
myOrder = {};

Example:

myOrder = {
    "name of product" : "earbuds", 
    "cost" : "799", 
    "warranty" : "1 year"
};

Accessing Object Values:

  • The object values can be accessed by using the dot (“.”) notation.
  • We can also access objects by using bracket([]) notation.

Example 1: In the below program we are accessing the object using “.” notation.

JavaScript

let myOrder, i;
 
// Object is created with name myOrder
myOrder = {
    "name_of_the_product": "Earbuds",
    "cost": "799",
    "warranty": "1 year "
};
 
// Accessing for particular detail
// from object myOrder
i = myOrder.name_of_the_product;
 
// It prints the detail of name
// of the product
console.log(i);

Output: 

Earbuds

Example 2:

JavaScript

let myOrder, i;
 
myOrder = {
    "name_of_product": "Earbuds",
    "cost": "799",
    "warranty": "1 year"
};
 
// Accessing object using [] notation
i = myOrder["name_of_product"];
 
console.log(i);

Output: 

Earbuds

Nesting of objects in JSON: Objects can be nested inside other objects having a unique access path. In the same document, the same field name can occur in objects which are nested. The access name must be unique. In short, the nested objects will be defined or assigned to other objects.

Example:

myOrder = {
    "name of product" : "earbuds", 
    "cost" : "799", 
    "warranty" : { 
        "warranty1" : "6 months", 
        "warranty2 : "12 months"
    }
};

In the above example, we have declared another object within the object.

Note: We can even access the nested objects using dot(“.”) notation.

Example:

 i = myOrder.warranty.warranty2;

or

 i = myOrder.warranty[warranty2];

Modify values Of object: To modify the values, we have two ways.

  • The values of the object can modify by using a dot(“.”) notation.
  • The values of the object can modify by using bracket (“[ ]”) notation.

Example of Dot Notation:

myOrder.warranty.warranty2 = "3 months";

Example of Bracket Notation:

i = myOrder.warranty[warranty2] = "3 months";

Delete Object Properties: We can delete the JSON object properties by using the “delete” keyword.

Example:

delete myOrder.warranty.warranty2;

Looping an Object: Looping can be done in two ways –

  • Looping of an object can be done by using a property for-in loop.
  • For looping an object we can even use brackets (“[]”) in the for-in loop property.

Example 1:

Javascript

let myOrder, a;
 
myOrder = {
    "name of product": "earbuds",
    "cost": "799"
    "warranty": "1 year"
};
 
for (a in myOrder) {
 
    // Accessing loop object 
    // using dot notation
    console.log(myOrder.a);
}

Output: 

name of product
cost
warranty

Example 2: In the below example we are accessing a looping object using bracket[] notation.

JavaScript

let myOrder, a;
 
myOrder = {
    "name_of_product": "earbuds",
    "cost": "799",
    "warranty": "1 year"
};
 
for (a in myOrder) {
 
    // Accessing object in looping
    // using bracket notation
    console.log(myOrder[a]);
}

Output: 

earbuds
799
1 year
Whether you’re preparing for your first job interview or aiming to upskill in this ever-evolving tech landscape, CodeConfig.in Courses are your key to success. We provide top-quality content at no cost, all geared towards accelerating your growth in a time-bound manner. Join the millions we’ve already empowered, and we’re here to do the same for you. Don’t miss out – check it out now!

Explore More

How to Center a Popup Window on Screen

JavaScript window.open() method is used to open a popup window. This popup window will be placed in the center of the screen. This example creates the pop-up window without placing it into

How to hide URL in the popup window opened using window.open

If you are using below code to open a popup window in your web page, then address must be appearing in you pop up window and f you want to

window.showModalDialog is deprecated in Edge and Chrome

If you have a website being compatible with Edge/Chrome and in past it was only compatible with IE 11 and if you are using window.showModalDailog in your JavaScript code, then