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WebSocket: open event

The open event is fired when a connection with a WebSocket is opened.

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

js

addEventListener("open", (event) => {});

onopen = (event) => {};

Event type

A generic Event.

Examples

js

// Create WebSocket connection.
const socket = new WebSocket("ws://localhost:8080");

// Connection opened
socket.addEventListener("open", (event) => {
  socket.send("Hello Server!");
});

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
open_event 5 12 7 10 12.1 5 ≤37 18 7 12.1 4.2 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/WebSocket/open_event