JavaScript objects and methods

Hi there. Welcome to another edition of this exciting JavaScript series. In the previous lesson, we were looking at an introduction to JavaScript, and in this lesson, we shall move on by looking at objects and methods. These two are very necessary in the study of JS. If you are new to this platform, don’t forget to check on our previous lessons. Also subscribe to our YouTube channel.

Just like in many other programming languages, objects in JavaScript can be compared to real life objects with various characteristics or properties. For example, a book has properties like color, shape, size, and so on. Hence, in JS, an object can be defined as a stand-alone entity with properties and types. 

To create an object, we declare a variable and give it a name, after which we open the curly brace “{” where we write our properties. When you are done, you close the curly brace “}”and then you end with a semicolon. When listing the properties, it should be done in such a way that each property is on a separate line, and each line should end with a comma “,”. Let’s consider the example below.

var myBook = {
color: “blue”,
size : “A4”,
weight: 0.1,
};

We can display the contents of object on the console by simply typing the name of the object. In our case, we will be typing “myBook”. After typing, it produces the following output:

To access the property of an object, we type the object name, add a dot, and then the property name. That is 

objectName.propertyName

Let us apply this in our example above to get the color property. We have 

myBook.color

The code gives the following output :

On the other hand, a method is simply a function inside an object. In other words, it is a function that is a property of an object. Let’s take our above example further by adding a method that alerts a message when called. 

var myBook = {
color: “blue”,
size : “A4”,
weight: 0.1,
show: function(message) {
alert(message);
},
};

To access a method, you begin by typing the name of the object, followed by a dot, the property name bearing the function and finally the brackets. That is

myBook.show(“Hello”)

The code produces the following output when typed on the console:

Hope you had fun while writing the codes and see them actually working? In our next lesson, we will be looking at something else. Have a nice time coding.