JSON Object Literals
This is a JSON string:
'{"name":"John", "age":30, "car":null}'
Inside the JSON string there is a JSON object literal:
{"name":"John", "age":30, "car":null}
JSON object literals are surrounded by curly braces {}.
JSON object literals contains key/value pairs.
Keys and values are separated by a colon.
Keys must be strings,
and values must be a valid JSON data type:
string
number
object
array
boolean
null
Each key/value pair is separated by a comma.
It is a common mistake to call a JSON object literal "a JSON object".
JSON cannot be an object. JSON is a string format.
The data is only JSON when it is in a string format.
When it is converted to a JavaScript variable, it becomes a JavaScript object.
JavaScript Objects
You can create a JavaScript object from a JSON object literal:
Example
myObj = {"name":"John", "age":30, "car":null};
Try it Yourself »
Normally, you create a JavaScript object by parsing a JSON string:
Example
myJSON = '{"name":"John", "age":30, "car":null}';
myObj = JSON.parse(myJSON);
Try it Yourself »
Accessing Object Values
You can access object values by using dot (.) notation:
Example
const myJSON = '{"name":"John", "age":30, "car":null}';
const myObj = JSON.parse(myJSON);
x = myObj.name;
Try it Yourself »
You can also access object values by using bracket ([]) notation:
Example
const myJSON = '{"name":"John", "age":30, "car":null}';
const myObj = JSON.parse(myJSON);
x = myObj["name"];
Try it Yourself »
Looping an Object
You can loop through object properties with a for-in loop:
Example
const myJSON = '{"name":"John", "age":30, "car":null}';
const myObj = JSON.parse(myJSON);
let text = "";
for (const x in myObj) {
text += x + ", ";
}
Try it Yourself »
In a for-in loop, use the bracket notation to access the property values:
Example
const myJSON = '{"name":"John", "age":30, "car":null}';
const myObj = JSON.parse(myJSON);
let text = "";
for (const x in myObj) {
text += myObj[x] + ", ";
}
Try it Yourself »
★
+1
Reference: https://www.w3schools.com/js/js_json_objects.asp
JSON Object Literals
JavaScript is the world's most popular programming language.
JavaScript is the programming language of the Web.
JavaScript is easy to learn.
This tutorial will teach you JavaScript from basic to advanced.
JavaScript is the programming language of the Web.
JavaScript is easy to learn.
This tutorial will teach you JavaScript from basic to advanced.