JSON Array Literals

This is a JSON string:

'["Ford", "BMW", "Fiat"]'

Inside the JSON string there is a JSON array literal:

["Ford", "BMW", "Fiat"]

Arrays in JSON are almost the same as arrays in JavaScript.

In JSON, array values must be of type string, number, object, array, boolean or null.

In JavaScript, array values can be all of the above, plus any other valid JavaScript expression, including functions, dates, and undefined.

JavaScript Arrays

You can create a JavaScript array from a literal:

myArray = ["Ford", "BMW", "Fiat"];

You can create a JavaScript array by parsing a JSON string:

myJSON = '["Ford", "BMW", "Fiat"]';
myArray = JSON.parse(myJSON);

You access array values by index:

myArray[0];

Objects can contain arrays:

{
"name":"John",
"age":30,
"cars":["Ford", "BMW", "Fiat"]
}

You access array values by index:

myObj.cars[0];

You can access array values by using a for in loop:

for (let i in myObj.cars) {
x += myObj.cars[i];
}

Or you can use a for loop:

for (let i = 0; i < myObj.cars.length; i++) {
x += myObj.cars[i];
}