[Fixed] How to trigger window.onerror in angular?


I know there are many other posts about this topic, but I still can’t get it working.
I am using Angular 8 in my project and I want to send the browser console message to a server log file.
Could someone please clearifiy does questions for me:

  1. When does the window.onerror get trigged? – right know I put the function within the constructor, is that ok so?
    Does it get trigged, if I serve the project local?
  window.onerror = function (errorMsg, url, lineNumber) {
      alert(errorMsg + ' ' + lineNumber);
  1. What do I have to do to get it triggered? (or does for example a thrown error of a missing certificate – trigger this function?)

console.error(‘test’) – does this trigger it?

throw new Error() – or this?

  1. Does Console-Errors like CORS will trigger this function?
  2. I also read that it would get triggered if an img or script source is not avilable.

app.compentent.html: <img src="test.png">

app.copmentent.ts in the constructor (the code of point one)

But I still don’t get the alert to display.

I am grateful for any help – thanks


The following may work for you. I used it in some Vue.js code to test triggering window.onerror(). Using eval() should allow you to bypass the compile-time checks of Angular and putting it in window.onload() will ensure it is evaluated after page load.

window.onerror = function (message, source, lineno, colno, error) {
  alert('onerror called: ' + message);

window.onload = function () {

As a security note, don’t use eval() in production, especially if user input could get anywhere near it.

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