Get your own website Result Size: 625 x 565
x
 
<!DOCTYPE html>
<html>
<body>
<form id="myForm" name="form1" action="/action_page.php">
  First name: <input type="text" name="fname" value="Donald"><br>
  Last name: <input type="text" name="lname" value="Duck"><br>
  <input type="submit" value="Submit">
</form>
<p>Click the "Try it" button to change the value of the name attribute in the form element.</p>
<button onclick="myFunction()">Try it</button>
<p id="demo"></p>
<script>
function myFunction() {
  document.getElementById("myForm").name = "newName";
  document.getElementById("demo").innerHTML = "The name of the form was changed from 'form1' to 'newName'.";
}
</script>
</body>
</html>