EventSource.readyState

The readyState read-only property of the EventSource interface returns a number representing the state of the connection.

Syntax

var myReadyState = eventSource.readyState;

Value

A number representing the state of the connection. Possible values are:

  • 0 — connecting
  • 1 — open
  • 2 — closed

Examples

var 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

Specification Status Comment
HTML Living Standard
The definition of 'readyState' in that specification.
Living Standard Initial definition

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
EventSource support 6 No support 6.0 (6.0) No support (Yes) 5
Available in shared and dedicated workers[1] (Yes) No support 53.0 (53.0) No support (Yes) (Yes)
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
EventSource support 4.4 45 No support 12 4.1
Available in shared and dedicated workers[1] (Yes) 53.0 (53.0) No support (Yes) (Yes)

[1] But not service workers as yet.

See also

Document Tags and Contributors

 Contributors to this page: suda, chrisdavidmills
 Last updated by: suda,