javascript: how to display script errors in a popup alert?

Question

I want to display script errors in a popup alert instead of showing them in the browser console.

window.onerror = function() {   var message = /* get error messages and put them here */;   alert(message);   return true; }; 

Answer 1

Yes, that is the correct way.

See the reference here:

http://www.javascriptkit.com/javatutors/error2.shtml

And explanation of how to see more details of the error here:

http://www.javascriptkit.com/javatutors/error3.shtml

Their example:

window.onerror = function(msg, url, linenumber) {     alert('Error message: '+msg+'\nURL: '+url+'\nLine Number: '+linenumber);     return true; } 

If you wish to display a LIST of errors in a single pop-up, it's trickier.

Since the errors occue 1 by 1, you need to do the following:

• have window.onerror handler store error details in some array

• Check that array periodically - either via a timer, or on every N'th call of window.onerror handler, or both.

  When the check happens, process entire array, display contents as desired, and empty out an array

Answer 2

Just in case someone would like to use it with jQuery:

$(window).on("error", function(evt) {      console.log("jQuery error event:", evt);     var e = evt.originalEvent; // get the javascript event     console.log("original event:", e);     if (e.message) {          alert("Error:\n\t" + e.message + "\nLine:\n\t" + e.lineno + "\nFile:\n\t" + e.filename);     } else {         alert("Error:\n\t" + e.type + "\nElement:\n\t" + (e.srcElement || e.target));     } });