Window: online event

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 addEventListener():

addEventListener("online", (event) => { })

Alternatively, assign to the event handler property of the interface:

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:

• HTMLBodyElement
• HTMLFrameSetElement
• SVGSVGElement

Examples

// addEventListener version
window.addEventListener("online", (event) => {
  console.log("You are now connected to the network.");
});

// ononline version (but note that this replaces other event listeners
// added using ononline, if any)
window.ononline = (event) => {
  console.log("You are now connected to the network.");
};

Specifications

Browser compatibility

See also

• offline