EventSource.onopen

The onopen property of the EventSource interface is an event handler called when an open event is received, that is when the connection was just opened.

Syntax

eventSource.onopen = function

Examples

evtSource.onopen = function() {
  console.log("Connection to server opened.");
};

Note: You can find a full example on GitHub — see Simple SSE demo using PHP.

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
onopen
6
79
6
No
Yes
5
≤37
18
45
12
5
1.0

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/EventSource/onopen