JSON Array Literals
JSON array represents ordered list of values.
JSON array can store multiple values.
It can store string, number, boolean or object in JSON array.
In JSON array, values must be separated by comma.
Example of JSON string containing a JSON array literal:
'["Ford", "BMW", "Fiat"]'
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.
JSON Array Literal of Strings
The string values must be enclosed within double quote and comma-separated.
["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"]
JSON Array Literal of Numbers
Numbers must me comma-separated.
[12, 34, 56, 43, 95]
JSON Array Literal of Booleans
Booleans must me comma-separated.
[true, true, false, false, true]
JSON Array Literal of Objects
{
"employees":[
{"name":"Tom", "email":"[email protected]"},
{"name":"John", "email":"[email protected]"},
{"name":"Logan", "email":"[email protected]"},
{"name":"Ryan", "email":"[email protected]"}
]
}
JSON Multidimensional Array
It is an array of arrays.
[
[ "a", "b", "c" ],
[ "d", "e", "f" ],
[ "g", "h", "i" ]
]
Convert JSON Array Literal to JavaScript Array
You can create a JavaScript array from a literal:
let myArray = ["Ford", "BMW", "Fiat"];
You can create a JavaScript array by parsing a JSON string:
let myJSON = '["Ford", "BMW", "Fiat"]';
let myArray = JSON.Parse(myJSON);
Accessing Array Values
You access array values by index:
let value = myArray[0];
Arrays in Objects
Objects can contain arrays:
{
"name":"Tom",
"surname":"Smith",
"cars":["Ford", "BMW", "Fiat"]
}
You access array values by index:
myObj.cars[0];
Looping Through an Array
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];
}