PromiseRejectionEvent
The PromiseRejectionEvent
interface represents events which are sent to the global script context when JavaScript Promise
s are rejected. These events are particularly useful for telemetry and debugging purposes.
For details, see Promise rejection events.
Constructor
PromiseRejectionEvent()
-
Creates a
PromiseRejectionEvent
event, given the type of event (unhandledrejection
orrejectionhandled
) and other details.
Instance properties
Also inherits properties from its parent Event
.
PromiseRejectionEvent.promise
Read only-
The JavaScript
Promise
that was rejected. PromiseRejectionEvent.reason
Read only-
A value or
Object
indicating why the promise was rejected, as passed toPromise.reject()
.
Instance methods
This interface has no unique methods; inherits methods from its parent Event
.
Events
rejectionhandled
-
Fired when a JavaScript
Promise
is rejected, and after the rejection is handled by the promise's rejection handling code. unhandledrejection
-
Fired when a JavaScript
Promise
is rejected but there is no rejection handler to deal with the rejection.
Examples
This simple example catches unhandled promise rejections and logs them for debugging purposes.
js
window.onunhandledrejection = (e) => {
console.log(e.reason);
};
Specifications
Specification |
---|
HTML Standard # the-promiserejectionevent-interface |
Browser compatibility
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