Note: This feature is available in Web Workers.
The PromiseRejectionEvent() constructor returns a new PromiseRejectionEvent object, which represents events fired when a JavaScript Promise is rejected.
With promise rejection events, it becomes possible to detect and report promises which fail and whose failures go unnoticed. It also becomes easier to write a global handler for errors.
There are two types of PromiseRejectionEvent: unhandledrejection is sent by the JavaScript runtime when a promise is rejected but the rejection goes unhandled. A rejectionhandled event is emitted if a promise is rejected but the rejection is caught by a rejection handler.
new PromiseRejectionEvent(type, options)
type
A string with the name of the event. It is case-sensitive and browsers set it to rejectionhandled or unhandledrejection.
options
An object that, in addition of the properties defined in Event(), can have the following properties:
promise
The Promise that was rejected.
reason
Any value or Object which represents the reason the promise was rejected. This can be anything from a numeric error code to an error string to an object which contains detailed information describing the situation resulting in the promise being rejected.
A new PromiseRejectionEvent object configured as specified by the parameters.
This example creates a new unhandledrejection event for the promise myPromise with the reason being the string "My house is on fire". The reason could just as easily be a number, or even an object with detailed information including the home address, how serious the fire is, and the phone number of an emergency contact who should be notified.
let myRejectionEvent = new PromiseRejectionEvent("unhandledrejection", {
promise: myPromise,
reason: "My house is on fire",
});
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4