JSON - JavaScript Object Notation

JSON

JavaScript Object Notation

Objects In JavaScript

• Object Literal: A JavaScript object literal is a comma-separated list of name-value pairs wrapped in curly braces.

const person = {
  name: "mohammed",
  lastname: "Alaoui",
  age: 26
};

JSON: JavaScript Object Notation

• What Is JSON ?

• JSON Data Representation format.

• JSON is a lightweight format for storing and transporting data.

• JSON is often used when data is sent from a server to a web page.

Why Use JSON?

• Commonly used for API & Configs.
• Lightweight & easy to read/Write.
• Integrates easily with most languages.

How To Write JSON?

1. Use Key/Value Pairs.
2. Use double quotes around key.
3. Use only specified data types.

{
  //objects
  "name": "Salah", //string
  "age": 22, //numbers
  "isStudent": true, //booleans
  "friends": [
    //arrays
    {
      "name": "friend1",
      "age": 0.5 //floating numbers
    },
    {
      "name": "friend2",
      "age": -45, //signed numbers
      "isStudent": false
    }
  ],
  "salary": null //and null
}

Data types

• Object.
• Numbers: 0, -5, 25.6,33.
• String: text.
• Boolean: true or false.
• Array.
• Null.

JavaScript function for JSON

• JSON.Parse()

Imagine we received this text from a web server:
'{ "name":"John", "age":30, "city":"New York"}'
We use JSON.parse() to convert text into a JavaScript object:

var object = JSON.parse('{"name":"John", "age":30, "city":"New York"}');

JSON.Stringfy()

Now Imagine we have to send this object to the web server again:
We use the JavaScript function JSON.stringify() to convert it into a string.

var myJSON = JSON.stringify(object);