React to clicks, input and more.
✍️ 3 exercises + code challenge in this lessonAn event is something that happens on the page: a click, a key press, a form submission, the page finishing loading.
click, dblclick, mouseover, mouseoutinput, change, submit, focus, blurkeydown, keyupload, DOMContentLoadedAttach handlers with element.addEventListener("click", handler). It keeps JavaScript out of your HTML and allows several handlers per event.
Mastering JavaScript Events helps you write clean and reliable JavaScript code. Follow standard conventions, test edge cases, and keep logic simple. Try running the code example below and complete the exercises to build confidence.
<input id="name" placeholder="Type your name">
<p id="hello">Hello!</p>
<button id="btn">Click me</button>
<p id="count">Clicks: 0</p>
<script>
let clicks = 0;
document.getElementById("name").addEventListener("input", (e) => {
document.getElementById("hello").textContent = "Hello, " + (e.target.value || "!");
});
document.getElementById("btn").addEventListener("click", () => {
clicks++;
document.getElementById("count").textContent = "Clicks: " + clicks;
});
</script>Check what you learned in “JavaScript Events”.
Run a function when the button is clicked.
button.("click", handleClick);
Which event fires every time the value of an input changes while typing?
When the button is clicked, set the text of #msg to "Clicked!". (The check clicks the button for you.)
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