Object Properties

Overview.

In JavaScript, objects are a fundamental part of the language and are used to store data in key-value pairs. An object's properties are the values associated with a key, and can be accessed using the dot notation or bracket notation [].

Syntax

The syntax for accessing object properties is as follows:

objectName.propertyName;
objectName["propertyName"];

Parameter

The parameter for accessing object properties is the name of the property that you want to access. It can be a string or a variable that holds a string value.

Examples

Let's take a look at some examples of how to access object properties:

// Creating an object
const car = {
  make: "Toyota",
  model: "Camry",
  year: 2022
};

// Accessing object properties using dot notation
console.log(car.make); // Output: Toyota

// Accessing object properties using bracket notation
console.log(car["model"]); // Output: Camry

Uses cases with examples

Retrieving and displaying data from an object:

// Creating an object with employee details
const employee = {
  name: "John Doe",
  age: 30,
  designation: "Software Engineer",
  department: "IT"
};

// Displaying employee details
console.log(`Name: ${employee.name}`);
console.log(`Age: ${employee.age}`);
console.log(`Designation: ${employee.designation}`);
console.log(`Department: ${employee.department}`);

Dynamically accessing object properties using variables:

// Creating an object
const car = {
  make: "Toyota",
  model: "Camry",
  year: 2022
};

// Creating a variable to hold the property name
const propertyName = "make";

// Accessing object properties using bracket notation and a variable
console.log(car[propertyName]); // Output: Toyota

Notes

• Object properties can hold any type of data, including numbers, strings, booleans, arrays, and even other objects.
• If you try to access a property that does not exist, the value returned will be undefined.
• Object properties can be added, modified, or deleted using the dot notation or bracket notation.

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