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

Javascript Web Development Object Oriented Programming

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

Example

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initialscale=1.0">
<title>Document</title>
<link rel="stylesheet" href="//code.jquery.com/ui/1.12.1/themes/base/jquery-ui.css">
<script src="https://code.jquery.com/jquery-1.12.4.js"></script>
<script src="https://code.jquery.com/ui/1.12.1/jquery-ui.js"></script>
</head>
<body>
<button class="clickTheButton">Click The Button to get an
alert</button>
<script>
   for (var clickButton of
   document.getElementsByClassName("clickTheButton"))
   clickButton.addEventListener("click", alertMeessage);
   function alertMeessage() {
      alert("You have clicked the button");
   }
</script>
</body>
</html>

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.

Output

This will produce the following output −

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

AmitDiwan

Updated on: 10-Sep-2020

1K+ Views

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