The EventSource() constructor returns a newly-created EventSource, which represents a remote ressource.


pc = new EventSource(url, configuration);


A USVString that represents the location of the remote ressource
configuration Optional
Provides options to configure the new connection. The possible entries are:
  • withcredentials, defaulting to false, indicating if CORS should be set to include credentials.

Return value

A newly-created EventSource object, configured as described by configuration, if specified; otherwise, configured to appropriate basic defaults.


Specification Status Comment
WHATWG HTML Living Standard
The definition of 'EventSource()' in that specification.
Living Standard Initial definition

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
 Basic support 9 6.0 (6.0) ? 11 5
CORS support (withCredentials) 26 11.0 (11.0) ? 12 ?
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 4.4 6.0 (6.0) ? ? ?
CORS support (withCredentials) ? 11.0 (11.0) ? ? ?

See also


© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.

API Constructor EventSource Reference Server-sent events