JSON Refresher

A quick refresher on JSON concepts

Photo by Chris Ried on Unsplash

The Basics

• JSON stands for JavaScript Object Notation
• It’s used for data representation and transmission
• Comprised of key-value pairs
• Text-based
• Minimal and portable
• Based on conventions seen in many languages
• Code for parsing JSON is available in many languages

Syntax

• "key" : value
• Starts and ends with { }
• Keys are quoted
• Values can be strings, numbers, booleans, null, array, or objects containing these types
• Commas between pairs
• Syntax validators like https://jsonlint.com/ can be used

{
"firstName" : "Julie",
"lastName" : "Smith",
"course" : "Web Development",
"grade" : 92
}

How to Indicate an Array in JSON

Use the [ ] notation to indicate an array.

{
"firstName" : "Julie",
"lastName" : "Smith",
"course" : "Web Development",
"grades" : [92,88,91,85]
}

How to Indicate an Object in JSON