Question

Is there a way to retrieve the line number from an Internet Explorer 7/8 error object?

I’m only aware of the .message, .description and .number properties.

I’ve searched around a bit and found an MSDN article on .stack ( http://msdn.microsoft.com/en-us/library/hh699850(v=vs.94).aspx ), but even using their own example code doesn’t return a line number:

http://jsfiddle.net/LWevS/

Answer 1

I dug around some more and found that it is possible to retrieve the line number in IE using window.onerror. It’s not from the Error object itself, but it’s a decent workaround:

function BadFunction(){
    This.badcode.willnot.work = 1000
}

function ForceError(msg, url, lno) {
  alert("Error Occurred! Handled by Generic Error Handler" + "\n" +
     "Error: " + msg + "\n" + "URL: " + url + "\n" +   
     "Line Number: " + lno);

  return true;
}

window.onerror = ForceError;

This method requires that the error bubble up to the window. If you have a try/catch in your code, you will need to re-throw the error so it can bubble up.

I also came across StackTraceJS on GitHub while researching a solution to this problem. Their stack tracing script works great on all browsers except for Internet Explorer. A great run-time debugger if you want to log errors produced on the client browser.

http://stacktracejs.com/