JavaScript JSON and Local Storage

Question 1

What is JSON?

Answer 1

JavaScript Object Notation

Data interchange format used to send and store information in computer systems. Saves data after the web page has been closed

Question 2

What are serialization and deserialization?

Answer 2

Serialization converting a native object to a string so it can be transmitted across a network

Deserialization is converting a string to a native object

Question 3

How do you serialize a data structure into a JSON string using JavaScript?

Answer 3

JSON.stringify();

Question 4

How do you deserialize a JSON string into a data structure using JavaScript?

Answer 4

JSON.parse();

Question 5

How do you store data in localStorage?

Answer 5

localStorage.setItem();

You call the setItem method of the localStorage object with keyName and keyValue

Question 6

How do you retrieve data from localStorage?

Answer 6

localStorage.getItem();

You call the getItem method of the localStorage object with the keyName

Question 7

What data type can localStorage save in the browser?

Answer 7

strings

Question 8

When does the ‘beforeunload’ event fire on the window object?

Answer 8

When the page is refreshed or closed