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WebSocket: open event - Web APIs | MDN
WebSocket: open event
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
Note: This feature is available in Web Workers.
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
| Specification |
|---|
| WebSockets # dom-websocket-onopen |
Browser compatibility
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