×

Save to Google Drive

If you have a Google account, you can save this code to your Google Drive.

Google will ask you to confirm Google Drive access.

Warning: The 10th of June 2021, we will discontinue the ability to save to Google Drive.

You will still be able to access your stored code on Google Drive.

×

Open from Google Drive

If you have saved a file to Google Drive, you can open it here:

Warning: The 10th of June 2021, we will discontinue the ability to save to Google Drive.

You will still be able to access your stored code on Google Drive.

Result Size: 625 x 565
​x
 
<!DOCTYPE html>
<html>
<body>
​
<p>Click the button to check whether the variable y is defined or undefined.</p>
​
<button onclick="myFunction()">Try it</button>
​
<p id="demo"></p>
​
<script>
function myFunction() {
  if (typeof y === "undefined") {
��� txt = "y is undefined";
  } else {
��� txt = "y is defined";
  }
  document.getElementById("demo").innerHTML = txt;
}
</script>
​
</body>
​
​
​
</html>
​
×

Report a Problem:

If you want to report an error, or if you want to make a suggestion, do not hesitate to send us an e-mail:

help@w3schools.com