JavaScript Objects

 In JavaScript, almost "everything" is an object.

  • Booleans can be objects (if defined with the new keyword)
  • Numbers can be objects (if defined with the new keyword)
  • Strings can be objects (if defined with the new keyword)
  • Dates are always objects
  • Maths are always objects
  • Regular expressions are always objects
  • Arrays are always objects
  • Functions are always objects
  • Objects are always objects

All JavaScript values, except primitives, are objects.

JavaScript Object Properties

Properties are the most important part of any JavaScript object.

JavaScript Properties

Properties are the values associated with a JavaScript object.

A JavaScript object is a collection of unordered properties.

Properties can usually be changed, added, and deleted, but some are read only.

Accessing JavaScript Properties

The syntax for accessing the property of an object is:

objectName.property      // person.age

or

objectName["property"]   // person["age"]

or

objectName[expression]   // x = "age"; person[x]

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