Chapter 5: Objects

Everything in JavaScript is either one of the six primitive data types we met in Chapter 2 (strings, numbers, booleans, symbols, undefined, and null) or an object. We’ve actually met some objects already; arrays in Chapter 3 and functions in Chapter 4 are both objects, although these are built-in objects that are part of the language. In this chapter we’re going to look at user-defined objects, as well as some of the other built-in objects.

In this chapter, we’ll cover the following topics:

  • Object literals

  • Adding properties to objects

  • Object methods

  • JSON

  • The Math object

  • The Date object

  • The RegExp object

  • Project ― we'll create quiz and question objects and ask random questions

Object Literals

An object in JavaScript ...

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