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 wasClean read-only property of the CloseEvent interface returns true if the connection closed cleanly.
A boolean value. True if the connection closed cleanly, false otherwise.
The following example prints the value of wasClean to the console.
WebSocket.onclose = (event) => {
console.log(event.wasClean);
};
| Specification |
|---|
| WebSockets> # ref-for-dom-closeevent-wasclean②> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
wasClean |
15 | 12 | 8 | 12.1 | 6 | 18 | 8 | 12.1 | 6 | 1.0 | 4.4 | 6 |
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https://developer.mozilla.org/en-US/docs/Web/API/CloseEvent/wasClean