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 only available in Web Workers.
The error event of the WorkerGlobalScope interface fires when an error occurs in the worker.
Use the event name in methods like addEventListener(), or set an event handler property.
addEventListener("error", (event) => { })
onerror = (message, filename, lineno, colno, error) => { }
Note: For historical reasons, onerror on Window and WorkerGlobalScope objects is the only event handler property that receives more than one argument.
For more details about this, see the page for the error event on Window objects.
A generic Event.
The following code snippet shows an onerror handler set inside a worker:
self.onerror = () => {
console.log("There is an error inside your worker!");
};
The same snippet, but using addEventListener():
self.addEventListener("error", () => {
console.log("There is an error inside your worker!");
});
| Specification |
|---|
| HTML> # handler-workerglobalscope-onerror> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
error_event |
4 | 12 | 3.5 | 11.5 | 4 | 18 | 4 | 14 | 5 | 1.0 | 4.4 | 5 |
The WorkerGlobalScope interface it belongs to.
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https://developer.mozilla.org/en-US/docs/Web/API/WorkerGlobalScope/error_event