EventSource: readyState property

{{APIRef("Server Sent Events")}}{{AvailableInWorkers}}

The readyState read-only property of the {{domxref("EventSource")}} interface returns a number representing the state of the connection.

Value

A number which is one of the three possible state constants defined on the {{domxref("EventSource")}} interface:

• EventSource.CONNECTING (0)
  • : The connection is not yet open.
• EventSource.OPEN (1)
  • : The connection is open and ready to communicate.
• EventSource.CLOSED (2)
  • : The connection is closed or couldn't be opened.

Examples

const evtSource = new EventSource("sse.php");
console.log(evtSource.readyState);

[!NOTE] You can find a full example on GitHub — see Simple SSE demo using PHP.

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• {{domxref("EventSource")}}