HTML onoffline Event Attribute - HTML Window Event Attributes

Definition and Usage

The onoffline attribute fires when the browser's connection status changes from online to offline.

Tip: The onoffline attribute is the opposite of the ononline attribute.

Browser Support

The numbers in the table specify the first browser version that fully supports the event attribute.

Syntax

<element onoffline="script">

Attribute Values

Value	Description
script	The script to be run on onoffline

Technical Details

Supported HTML tags:	<body>

Example of HTML onoffline Event Attribute

Here executes a JavaScript when the browser changes from working online to working offline.

index.html

Example: HTML

<!DOCTYPE html>
<html>
<body ononline="onFunction()" onoffline="offFunction()">

<p>Try to disconnect from the internet to toggle between working online and offline.</p>

<script>
function onFunction() {
  alert ("Your browser is working online.");
}

function offFunction() {
  alert ("Your browser is working offline.");
}
</script>

</body>
</html>

Output should be:

How to add a JavaScript when the browser changes from working online to working offline

Try to disconnect from the internet to toggle between working online and offline.

index.html

Example: HTML

<!DOCTYPE html>
<html>
<body ononline="onFunction()" onoffline="offFunction()">

<p>Try to disconnect from the internet to toggle between working online and offline.</p>

<script>
function onFunction() {
  alert ("Your browser is working online.");
}

function offFunction() {
  alert ("Your browser is working offline.");
}
</script>

</body>
</html>

Output should be:

html event attributes

Type:	Develop
Category:	Web Tutorial
Sub Category:	HTML Window Event Attributes
Uploaded by:	Admin

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