JavaScript JSON

JSON (JavaScript Object Notation) is a lightweight data interchange format inspired by JavaScript object literal syntax.

It is commonly used for transmitting data between a server and a web application, as well as for storing and exchanging data in various applications and platforms.

Example

  "name": "John Doe",
  "age": 30,
  "isStudent": false,
  "address": {
    "street": "123 Main St",
    "city": "Anytown",
    "country": "USA"
  },
  "skills": ["JavaScript", "HTML", "CSS"]
}

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Output

Data types in JSON

Objects: Enclosed in curly braces {}, consisting of key-value pairs separated by commas.
Arrays: Ordered lists of values enclosed in square brackets [].
Strings: Enclosed in double quotes " ".
Numbers: Integers or floating-point numbers.
Boolean values: true or false.
Null: Represents an empty value.

JSON Objects

JSON objects are written inside curly braces.

Just like in JavaScript, objects can contain multiple name/value pairs:

Example

{"firstName":"John", "lastName":"Doe"}

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Output

JSON Arrays

JSON arrays are written inside square brackets.

Just like in JavaScript, an array can contain objects:

Example

"employees":[
  {"firstName":"John", "lastName":"Ram"},
  {"firstName":"Anna", "lastName":"Sohan"},
  {"firstName":"Peter", "lastName":"Mohan"}
]

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Output

Converting a JSON Text to a JavaScript Object

A common use of JSON is to read data from a web server, and display the data in a web page.

For simplicity, this can be demonstrated using a string as input. Just like in JavaScript, an array can contain objects:

Example

let text = '{ "employees" : [' +
'{ "firstName":"John" , "lastName":"Doe" },' +
'{ "firstName":"Anna" , "lastName":"Smith" },' +
'{ "firstName":"Peter" , "lastName":"Jones" } ]}';

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