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Window: online event - Web APIs | MDN
Window: online event
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The online event of the Window interface is fired when the browser has gained access to the network and the value of Navigator.onLine switches to true.
Note: This event shouldn't be used to determine the availability of a particular website. Network problems or firewalls might still prevent the website from being reached.
Syntax
Use the event name in methods like addEventListener(), or set an event handler property.
js
addEventListener("online", (event) => { })
ononline = (event) => { }
Event type
A generic Event.
Event handler aliases
In addition to the Window interface, the event handler property ononline is also available on the following targets:
Examples
js
// addEventListener version
window.addEventListener("online", (event) => {
console.log("You are now connected to the network.");
});
// ononline version
window.ononline = (event) => {
console.log("You are now connected to the network.");
};
Specifications
| Specification |
|---|
| HTML # event-online |
| HTML # handler-window-ononline |
Browser compatibility
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