The unhandledrejection event is fired when a JavaScript Promise is rejected but there is no rejection handler to deal with the rejection.
Inheritance
The unhandledrejection event implements the PromiseRejectionEvent interface, which inherits from Event. You can use the properties and methods defined on these interfaces.
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a:hover text { fill: #0095DD; pointer-events: all;}
Examples
window.addEventListener("unhandledrejection", function (event) {
console.warn("WARNING: Unhandled promise rejection. Shame on you! Reason: "
+ event.reason);
});
Specifications
Browser compatibility
| Feature |
Chrome |
Firefox (Gecko) |
Internet Explorer |
Opera |
Safari |
| Basic support |
49 |
No support[1] |
No support |
No support |
No support |
| Feature |
Android |
Firefox Mobile (Gecko) |
IE Mobile |
Opera Mobile |
Safari Mobile |
| Basic support |
No support |
No support[1] |
No support |
No support |
No support |
[1] In Firefox, this is implemented but disabled by default. To turn it on, go to about:config and set the dom.promise_rejection_events.enabled pref to true.
See also
Document Tags and Contributors