JavaScript how to get an alert to appear when I click on a button in a class?

For this, use the document.getElementByClassName(). Following is the code −


 Live Demo

<!DOCTYPE html>
<html lang="en">
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initialscale=1.0">
<link rel="stylesheet" href="//">
<script src=""></script>
<script src=""></script>
<button class="clickTheButton">Click The Button to get an
   for (var clickButton of
   clickButton.addEventListener("click", alertMeessage);
   function alertMeessage() {
      alert("You have clicked the button");

To run the above program, save the file name “anyName.html(index.html)” and right click on the file. Select the option “Open with Live Server” in VS Code editor.


This will produce the following output −

When you click the button, an alert message will be visible. This will produce the following output −

Updated on: 10-Sep-2020

1K+ Views

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