Learn JavaScript Day 6: JavaScript events

Welcome to day 6 of your JavaScript journey! Today, we’re going to talk about JavaScript events, which are an important part of web development. Events are actions or occurrences that happen in the browser, such as a mouse click or a page load. By using JavaScript, we can detect and respond to these events in a dynamic and interactive way.

In this tutorial, we’ll cover some of the most common events in JavaScript, including click, hover, load, and more. We’ll also learn how to handle and use these events in our code to create dynamic and engaging web pages.

What are JavaScript events?

JavaScript events are actions or occurrences that happen in the browser. They can be triggered by user actions, such as a mouse click or a keyboard press, or by the browser itself, such as a page load or an error message.

Types of JavaScript events

There are many types of JavaScript events, but some of the most common include:

Click: When the user clicks on an element, such as a button or a link.
Hover: When the user moves the mouse over an element.
Load: When the page finishes loading.
Submit: When the user submits a form.
Keydown: When the user presses a key on the keyboard.
Resize: When the browser window is resized.

How to handle JavaScript events

To handle JavaScript events, we use event listeners. An event listener is a function that is called when an event occurs. We can attach an event listener to an element using the addEventListener() method.

For example, let’s say we have a button element with an id of “currentButton”. We can attach a click event listener to this button like this:

const currentButton = document.getElementById("currentButton");
currentButton.addEventListener("click", function() {
  alert("Button clicked!");
});

In this code, we’re using the addEventListener() method to attach a click event listener to the “currentButton” element. When the user clicks on this button, the function inside the addEventListener() method will be called, which will display an alert box with the message “Button clicked!”.

Using events to create interactivity

By using JavaScript events, we can create dynamic and interactive web pages. For example, we can use events to change the style of an element when the user hovers over it, or to show and hide content when the user clicks on a button.

Let’s take a look at an example. Suppose we have an image element with an id of “currentImage”. We want to change the image source when the user clicks on it. We can do this using a click event listener, like this:

const currentImage = document.getElementById("currentImage");
currentImage.addEventListener("click", function() {
  currentImage.src = "newImage.jpg";
});

In this code, we’re using a click event listener to detect when the user clicks on the “currentImage” element. When this event occurs, the function inside the addEventListener() method will be called, which will change the image source to “newImage.jpg”.

Conclusion

JavaScript events are a powerful feature that allow us to create dynamic and interactive web pages. By understanding how to handle and use events in JavaScript, we can create engaging user experiences that respond to user actions and events.

That’s it for today’s Learn JavaScript Day 6: JavaScript events! We covered some of the most common events in JavaScript, including onclick, onkeyup, onmouseover, onmouseout, onchange, onload, onfocus, and onblur. By understanding how events work and how to bind them to elements in the DOM, you can create dynamic and interactive webpages that respond to user input.

Join us tomorrow for Learn JavaScript Day 7, where we’ll dive deeper into JavaScript functions and explore how they can be used to modularize your code and make it more reusable. See you then!

If you’re interested in learning more about JavaScript events, check out the official Mozilla Developer Network (MDN) documentation

Learn JavaScript Day 6: JavaScript events