HTML form action and onsubmit validations with JavaScript?

Javascript Web Development Object Oriented Programming

Let’s see an example wherein we are validating input text onsubmit −

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>
<form onsubmit="return validateTheForm()" method="GET" action="https://mail.google.com/mail/">
<br/>
<input type="text" id="txtInput" value=""/>
<input type="submit" value="search"/>
</form>
<script>
   function validateTheForm(){
      var validation = (document.getElementById('txtInput').value == 'gmail');
      if(!validation){
         alert('Something went wrong...Plese write gmail intext box and click');
         return false;
      }
      return true;
   }
</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.