I was wondering if you could suggest a javascript debugger which works on Android webkit.
I was trying to inject the following code into Android Webkit but for some strange reason could not do it in the begining (i think it might have to do something with specificity but not sure)
document.body.style.color='#ff00ff';
you might want to take a look at weinre:
Try jsHybugger: http://www.jshybugger.org/
It lets you set breakpoints, singlestep, catch exceptions, and interact with the JS/DOM environment. You can use it from Eclipse or from a Chrome or Chrome-compatible debugger on the remote desktop. It can be used with apps that create their own webView.
However, you have to install a few files -- but probably no more complicated to use than weinre. it does extensively modify the JS files (on the fly, transparently to the user) to enable all this debugging -- webKit really should support javascript debugging natively.
Your question shows an issue with altering CSS, which weinre does well. I didn't see that weinre supported debugging javascript (ie breakpoints and singlestepping)
Related
Is there a method for interactive debugging JavaScript and TypeScript in Visual Studio using Chrome similar to the functionality currently provided with Internet Explorer? With IE I can set a breakpoint in JavaScript or TypeScript in the IDE and step through the code within the IDE. I cannot get that same behavior with Chrome in Visual Studio.
For a fully integrated debugging experience with any JavaScript/browser based application and Visual Studio, you'll need to use Internet Explorer today. As TypeScript compiles to JavaScript, the integrated debugging also requires Internet Explorer.
The "trick" I often use if I want to use another browser is to add a debugger; statement somewhere in my TypeScript/JavaScript code and have the development tools open in Chrome ..., and execution will then stop on that instruction. As long as you have source-maps enabled, you should see your original TypeScript code in the Chrome debugging window. You can then use Chrome debugging tools to set further breakpoints. If the file doesn't change, the breakpoints will be retained from a "refresh" of the page.
This does not allow me to set breakpoints within Visual Studio though, but it's still effective and works well enough for my development.
Update April 2016
As a few in comments have pointed out, there's a path to making this work a little better, although the experience isn't nearly as complete as it is for Internet Explorer. Follow the steps outlined here. It involves starting Chrome with a custom command line (to enable remote debugging):
chrome.exe --remote-debugging-port=9222
And then attaching to the Chrome process with WebKit debugging enabled. You can add a custom browser to make it easy to launch Chrome.
(But, I will add that I haven't been able to get this to work in a way that I find useful and consistent, especially as I use Chrome for most other web browsing.)
I am using Visual Studio 2010 Express Developer edition. Developing a Website. I'm using JavaScript in my .aspx pages. How to put breakpoints in Javascript.
Any help is highly appreciated.
Thank You
If you are using Web Developer Express you can do this within Visual Studio - here are the instructions.
If you are using a different Express edition, you will have to use a browser tool for client side debugging - for example Firebug. IE and Chrome have built in developer tools that have this kind of functionality.
You can use your browser's debugger :
For Firefox, you can use Firebug (http://getfirebug.com).
Chrome contains an embedded debugger.
From memory you will need to do the following to get JS debugging in Visual Studio:
Ensure that Internet Explorer has script debugging enabled (somewhere in tools -> options) - this is the bit most people don't know about.
Then go into the .aspx and add a breakpoint by clicking in the left margin of the line of Javascript you want to debug.
Launch the website project in debug mode (F5) and hit the page using IE - your breakpoint should then hit.
As noted by other people you can use a host of other (usually better) tools that come with other browsers.
If you're debugging IE, use the following links:
http://aspnetlive.blogspot.com/2010/02/debugging-java-script-in-visual-studio.html
http://msdn.microsoft.com/en-us/library/7seh8d72.aspx
For Firefox, I recommend Firebug.
http://getfirebug.com/
For Chrome, you can use the Developer's Tools debugger.
Update
Here's a comprehensive list of debugging JavaScript in each browser:
http://siliconforks.com/doc/debugging-javascript/
I like Firebug, plugin for Firefox.
I think the idea is to use the Attach to process option of the Debug menu; but to be honest, I've never had much luck getting VS to do this fluidly (though I remember it working at times, success is spasmodic at best), maybe tabbed browsing has made this an issue - I'm unsure.
One thing I can recommend, however, and we might get a few hecklers, are the Developer Tools of IE9. If nothing else, IE9 has become an invaluable tool for me recently simply because of its Javascript debugging capabilities. Here's an MSDN article to get you started with this.
Using FireBug & Internet Explorer Debuging tool let you debug and put breakpoint on your javascript files
Warning: I have very little JavsScript experience.
In my past programming experience, I usually have a standalone interpreter/compiler, a text editor and a command line to compile/run my software or my tests (I love test driven development). I really like it this way, since I have the feeling of being in complete control over the tools. However, editing JavaScript I need to put statements in a text file , open my web browser and click on reload. I don't feel comfortable with it, as I cannot really see what is going on (besides some alert boxes).
Can you suggest me (I'm on a Mac) another workflow? Perhaps with a debugger? Is there a standalone JavaScript interpreter?
Opera, Internet Explorer, Chrome and Safari all come with good debuggers built in (links go to information about the debuggers).
They are all modeled after Firebug, an extension for Firefox (and the existence of which is why Firefox doesn't have one built in).
Firebug has a javascript debugger,a console, and a command line. I couldn't live without it.
Firebug is a firefox extension. They do have firebug lite for other browsers.
As far as workflow goes... Ctrl+S, Alt+Tab, F5 over and over again.
I would throw in validation there as well, use jslint either via one of the available command line tools, or via eg. Aptana which has builtin validation.
Setting up a simple build script is also preferable. I do it with all my projects and lets it handle validation, conditional code (debug versions etc) and minifying.
This http://github.com/oyvindkinsey/easyXDM/blob/master/build.xml is for instance the build setup for easyXDM. It does everything from pushing out new versions to the website to creating documentation and zip files..
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?
Web Development Helper is very good.
The IE Dev Toolbar is often helpful, but unfortunately doesn't do script debugging
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.
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
I've found DebugBar.
Not as good as Firebug, but close.
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','http://getfirebug.com/releases/lite/1.2/firebug-lite-compressed.js');document.body.appendChild(firebug);(function(){if(window.firebug.version){firebug.init();}else{setTimeout(arguments.callee);}})();void(firebug);
See http://getfirebug.com/lite.html.
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):
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
Create a new empty web project inside of VWD
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)
Hit F5, IE will open up. Browse to the page you want to debug.
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.
IE8 has much improved developer tools. Until then it's best to write javascript for firefox first and then debug IE using alert() statements.
Microsoft Script Editor can be used to debug Javascript in IE. It's less buggy than Microsoft Script Debugger but has the same basic functionality, which unfortunately is pretty much limited to stepping through execution. I can't seem to inspect variables or any handy stuff like that. Also, it only shipped with Office XP/2003 for some bizarre reason. More info here if you're game.
I downloaded the Visual Web Developer 2008 Express Edition mentioned by Eugene Lazutkin but haven't had a chance to try it yet. I'd recommend trying that before Script Editor/Debugger.
It's not a full debugger, but my DP_DEBUG extensions provides some (I think) usful functionality and they work in IE, Firefox and Opera (9+).
You can "dump" visual representations of complex JavaScript objects (even system objects), do simplified logging and timing. The component provides simple methods to enable or disable it so that you can leave the debugger in place for production work if you like.
DP_Debug
The IE9 developer tools worked for me. Just set the "Browser Mode" menu item to IE7.
Hey I came across the same problem and found this the application IETESTER. It's pretty awesome, it's an app that has IE 5.5,6, and 7 bundled into it. It doesn't matter what IE version you currently have. This allows you to have multiple versions side by side.
If you enable javascript debugging in IE options and have Visual Studio installed you can even debug the javascript in VS with all the debug options available to you(watches, conditional breakpoints ,etc.)
If you want to start debugging before an error occurs you simply have to put the line
debugger;
into your JS code and this bring you into VS to begin debugging after this statement.
This is absolutely amazing to me for testing backward compatibility for JS code.
Use Internet Explorer 8. Then Try the developer tool.. You can debug based on IE 7 also in compatibility mode
FireBug Lite:
http://getfirebug.com/firebuglite
The answer is simple.
Get Internet Explorer 9
Press F12 to load up Developer Tools
Switch the browser mode to IE7
Running your code through a Javascript static analysis tool like JSLint can catch some common IE7 errors, such as trailing commas in object definitions.
IE8 Developer Tools are able to switch to IE7 mode
If you still need to Debug IE 7, the emulation mode of IE 11 is working pretty well.
Go to menu: Dev Tools, then to emulation and set it.
It also gives error line information.
The following tools works great for me:
1) http://www.debugbar.com/
Provide a convenience UI to with feature like source, style, DOM, Script, HTML check. It also show the actual error in your JS file (which line, which file).
2) http://www.my-debugbar.com/wiki/CompanionJS/Installing
Provide a console for IE6 or IE7 ( which originally does not support)
Screenshot
I have a few scripts on a site I recently started maintaining. I get those Object Not Found errors in IE6 (which Firefox fails to report in its Error Console?). What's the best way to debug these- any good cross-browser-compatible IDEs, or javascript debugging libraries of some sort?
There's no cross-browser JS debugger that I know of (because most browsers use different JS engines).
For firefox, I'd definitely recommend firebug (http://www.getfirebug.com)
For IE, the best I've found is Microsoft Script Debugger (http://www.microsoft.com/downloads/details.aspx?familyid=2f465be0-94fd-4569-b3c4-dffdf19ccd99&displaylang=en). If you have Office installed, you may also have Microsoft Script Editor installed. To use either of these, you need to turn on script debugging in IE. (uncheck Tools -> Internet Options -> Advanced -> Disable Script debugging).
You could also use Firebug Lite - which will work in IE & Opera. It's an external lib that will help you track down problems. It's sometimes more convenient than dealing with the MS Script Debugger.
Firebug
It's only for firefox but it should let you figure out what's happening on IE especially once you have the script line numbers.
You can use Visual Studio and enable debugging in browser
You can install FireBug plugin for Firefox, it's really good!
You can try to install IE8 beta 2 and use it in compatibility mode with built-in debugger.
Also in any line of your JS code you can write
debugger;
and this will be threated as breakpoint for any of the debug tools you use.
Cheers!
Aptana Studio provides JavaScript debugging for Firefox and IE
Firebug is the best all around client-side debugger. I frequently use it to debug CSS code as well as javascript. It allows you to easily find offending areas of code. I especially like the ability to modify tag attributes in the firebug pane and see the effects immediately before committing. Very useful for anyone designing websites.
You could use this tool apparently - Microsoft Script Debugger
Personally I try to go through the code and figure out what's going on - it gives you the line number where it goes wrong right?
To make the Microsoft Script Debugger more user friendly (and to add javascript error messages that actually are helpful to IE), I highly recommend Companion.JS.
Firebug seems to be the most useful so far. When a page is running on firebug, it can be very handy to log messages into firebug via javascript calls to console.log('your log message'); but don't execute that code in IE since the console object is only in scope when firebug is running.
For IE, other folks have mentioned the Script Debugger. Although it is not primarily for javascript debugging, it can be useful to also add the IE developer toolbar, which allows you to easily and dynamically inspect the style and other properties of your page's DOM.
In response to mopoke, for IE6 you definitely want to use Visual Studio for debugging if you can get it. For all intents and purposes, the MS script debugger is useless. You're better off using some form of tracing (not alerts) than using the MS script debugger. Dojo Toolkit, for instance, provides a debug console for tracing, but you can write your own by dumping messages to a secondary window or div.
The script debugger needlessly prompts you on each error in IE6 and even then doesn't give you enough state context to make it useful in a sufficiently complex JS app. Visual Studio is more tightly integrated and much friendlier. Just my experience.