How to catch uncaught exception in Promise

Question

Is there any way to globally catch all exceptions including Promise exceptions. Example:

    window.onerror = function myErrorHandler(errorMsg, url, lineNumb         


        

Answer 1

If you're writing code that can be executed both in a browser & in a Node.js environment, you could wrap your code in a self-executing function like this :

var isNode = (typeof process !== 'undefined' && typeof process.on !== 'undefined');
(function(on, unhandledRejection) {
    // PUT ANY CODE HERE
    on(unhandledRejection, function(error, promise) {
        console.error(`Uncaught error in`, promise);
    });
    // PUT ANY CODE HERE
})(
    isNode ? process.on.bind(process) : window.addEventListener.bind(window),
    isNode ? "unhandledRejection" : "unhandledrejection"
);

What would happen if you use this code :

• If you'd run it in a Node.js environment, your handler would be attached to the process object and be executed when you have an uncaught exception in a promise.

• If you'd run it in a browser environment, your handler would be attached to the window object and be executed when you have an uncaught exception in a promise and your browser supports the unhandledrejection event.

• If you'd run it in a browser environment without support for the unhandledrejection, you will not be able to catch your uncaught exception and your unhandledrejection event handler will never be triggered, but you would not get any errors if there's no uncaught exceptions.