Debugging JavaScript in IE7

Debugging JavaScript in IE7

I need to debug JavaScript in Internet Explorer 7.
Unfortunately, its default debugger doesn’t provide me with much information. It tells me the page that the error showed up on (not the specific script) and gives me a line number. I don’t know if that is related to my problem.
It’d be nice if it could narrow down the error to a line number on a specific script (like Firebug can).
Is there an addon to debug JavaScript in IE7 like Firebug does in Firefox?
Thank you!
See also:
Does IE7 have a “developer mode” or plugin like Firefox/Chrome/Safari?


Solution 1:

Web Development Helper is very good.

The IE Dev Toolbar is often helpful, but unfortunately doesn’t do script debugging

Solution 2:

The hard truth is: the only good debugger for IE is Visual Studio.

If you don’t have money for the real deal, download free Visual Web Developer 2008 Express EditionVisual Web Developer 2010 Express Edition. While the former allows you to attach debugger to already running IE, the latter doesn’t (at least previous versions I used didn’t allow that). If this is still the case, the trick is to create a simple project with one empty web page, “run” it (it starts the browser), now navigate to whatever page you want to debug, and start debugging.

Microsoft gives away full Visual Studio on different events, usually with license restrictions, but they allow tinkering at home. Check their schedule and the list of freebies.

Another hint: try to debug your web application with other browsers first. I had a great success with Opera. Somehow Opera’s emulation of IE and its bugs was pretty close, but the debugger is much better.

Solution 3:

you might want to try
microsoft script debugger
it’s pretty old but it’s quite useful in the sense if you stumble on any javascript error, the debugger will popup to show you which line is messing up. it could get irrating sometimes when you do normal surfing, but you can turn if off.

here’s a good startup on how to use this tool too.
HOW-TO: Debug JavaScript in Internet Explorer

Solution 4:

I’ve found DebugBar.

Not as good as Firebug, but close.

Solution 5:

In IE7, you can bring up firebug lite for the current page by pasting the following in the address bar:

javascript:var firebug=document.createElement('script');firebug.setAttribute('src','');document.body.appendChild(firebug);(function(){if(window.firebug.version){firebug.init();}else{setTimeout(arguments.callee);}})();void(firebug);


Solution 6:

Microsoft Script Editor is indeed an option, and of the ones I’ve tried one of the more stable ones — the debugger in IE8 is great but for some reason whenever I start the Developer Tools it takes IE8 a while, sometimes up to a minute, to inspect my page’s DOM tree. And afterwards it seems to want to do it on every page refresh which is a torture.

You can inspect contents of variables in Microsoft Script editor: if you poke around under Debug > Window you can turn on local variable inspection, watching etc.

The other option, Visual Web Dev, while bulky, works reasonably well. To set it up, do this (stolen from here):

  1. Debugging should be turned on in IE. Go into Tools > Internet Options > Advanced and check that Disable Script Debugging (Internet Explorer) is unchecked and Display a notification about every script error is checked
  2. Create a new empty web project inside of VWD
  3. Right-click on the site in the Solutions Explorer on the top right, go to Browse With and make sure your default browser is set to IE (it’s reasonable to assume if you’re a web developer IE is not your default browser in which case that won’t be the default.. by default)
  4. Hit F5, IE will open up. Browse to the page you want to debug.
  5. VWD will now open up any time you have a script error or if you set a breakpoint in one of the JS files. Debug away!

UPDATE: By the way, if you experience the same slowdowns as me with IE8’s otherwise decent debugger, there is a workaround — if you encounter or make IE encounter an error so that it pops up the “Do you want to debug” dialogue and hit Yes, the debugger will come up pretty much instantly. It seems like if you go “straight” into debugging mode the Dev Tools never inspect the DOM. It’s only when you hit F12 that it does.