This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The offline event of the Window interface is fired when the browser has lost access to the network and the value of Navigator.onLine switches to false.
Use the event name in methods like addEventListener(), or set an event handler property.
addEventListener("offline", (event) => { })
onoffline = (event) => { }
A generic Event.
In addition to the Window interface, the event handler property onoffline is also available on the following targets:
// addEventListener version
window.addEventListener("offline", (event) => {
console.log("The network connection has been lost.");
});
// onoffline version
window.onoffline = (event) => {
console.log("The network connection has been lost.");
};
| Specification |
|---|
| HTML> # event-offline> |
| HTML> # handler-window-onoffline> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
offline_event |
3 | 12 | 9 | 15 | 4 | 18 | 9 | 14 | 3 | 1.0 | 4.4 | 3 |
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https://developer.mozilla.org/en-US/docs/Web/API/Window/offline_event