Selectively Support Certain Browsers - javascript

Ok everyone, I have a requirement to only support IE 11+, Chrome 31+, etc. The specifics don't really matter at this point. I know it's not ideal to restrict other browsers, but this is a vendor requirement and isn't my call. I'm just trying to figure out how to go about doing this.
Initially I wanted to use feature detection (my assumption was that the site needed to be HTML5 compatible). These requirements have changed. Is feature detection still viable for this? I would prefer to not use user agent sniffing, since it's so easy to spoof.
I'm using ASP.NET, C#, .NET 4.0, jQuery, HTML5, CSS3
How can I accomplish this?
Thanks in advance!

You can look inside the Request server variable for useful information about the browser. While debugging, it looks to me like this is getting generated from the user agent. From what I know about the web though, this is how clients communicate to servers what they are capable of viewing.
There are a few properties that can help you within Request.Browser.
Request.Browser.Type //Returns "Chrome41"
Request.Browser.Browser // Returns "Chrome"
You could also use conditional comments for IE, something like this:
<!--[if IE 11]>
(Redirect users here or however you want to handle it)
<![endif]-->
I'm sure you've seen these before, but that statement basically is targeting any IE version less than 11. These are Microsoft / IE specific so while this will help you with your IE issue, you will most likely have to rely on the user agent or Request as above for other browsers.

Related

Force Employee To Use Firefox + Specified Version For Company Intranet

Please not not turn this into a discussion about which browser is better and the ethics of forcing a browser. It's an intranet, and it's what I am required to do so everyone calm down =o)
I need to prevent employees from trying to bypass the check to not use their preferred browser instead of the company mandated one + version. The decision was made based on security, compatibility, costs, and the use of company made Firefox extensions.
I came across this Force users to use Chrome/FireFox instead of IE which I can do easily in PHP to force use of Firefox, however it relies on the useragent which can easily be changed in numerous browsers and with the use of plugins.
Is there a JavaScript solution that I can use that DOES NOT check the useragent or any value that can be 'easily' modified by a user/plugin? It would need to detect if the browser is Firefox and what version it is. Site uses jQuery so if it can be done using that, however not required then by all means yes. I just am not aware of what ways to detect a browser and it's version that there are without checking useragent.
I remember way back in the day for detecting Netscape or some browser checking for document.all was used instead of useragent, so I'm guessing something similar, which only Firefox will have.
Thank you very much in advance!
Try this: http://jsfiddle.net/DerekL/62exH/
Because Firefox handles onpopstate differently than other browsers, you can then use this to detect if it is Firefox or not. This can not be changed by user or script. But the disadvantage is you can only get the version number by doing navigator.appVersion.
You can only try but cannot succeed in forcing a browser. That being said you can strip down the CSS in other browsers which may completely make your site close to unusable in other browsers.
To make your CSS only work with Firefox you can try approaches given # Targeting only Firefox with CSS

Can IE 9 still sign with Javascript like in old IE and Netscape / Firefox?

It was possible to sign with digital certificate in IE and Netscape
http://bozhobg.wordpress.com/2009/04/16/how-to-create-a-digital-signing-solution-with-only-javascript/
What's the equivalent in IE 9 ?
You're going to have a problem with this.
The clue is in the code in the link you provided. Specifically, where it uses new ActiveXObject().
ActiveX is a very old technology and it has severe security issues. For this reason, it's use has been discouraged for some time (this was the case a long time before the article you linked to was written).
IE9 does still support it, but only for legacy reasons; its use is strongly discouraged, and you will need to go to the browser config and disable some security settings in order to get it working.
If you do get activeX working in IE9, you'll also need to make sure you have the relevant activeX controls installed on your PC that actually do the work (I've not used the ones in question, so I can't advise on them). In addition, since the activeX technology is deprecated, you may find that the activeX control you need to use may not have been kept up-to-date. This may affect whether it works with newer versions of IE or Windows.

Best way to display warning message to "untested" browsers?

I have an app that I have fully tested in Safari 5, IE 9, FF6, and Chrome 14. I'm not looking to block or exclude any browsers from the experience. But I want to warn/inform users that there may be a better experience in another browser, and if they choose to continue, there may be features not working or broken.
I have looked at jQuery browser detection, but it seems to be a bit quirky. I know the best solution would be to warn based on feature detection, but we are currently in beta and I am not completely sure what features make or break. Such as web workers, its known that web workers not working breaks our app, but it works in IE lower versions. But then there is an issue with Opera that web workers is available, but not functioning correctly.
Ultimately I am looking for an easy way to say Browser X Version y and up don't show warning, and those and under show warning.
What is the best way to approach this?
Browser detection is indeed "a bit quirky", in pretty much any scenario. The jQuery route is probably as good as you're going to get, but as you say it's not great.
A better solution is generally to do feature detection, especially in cases like the one you describe where your site relies on specific features.
The best feature detection library is Modernizr. This will give you an bunch of Javascript flags which are set to true or false according to whether the browser supports a given feature. It detects support for a whole bunch of stuff, including Web Workers.
Check out this: http://www.w3schools.com/js/js_browser.asp
-Easy way of detecting the user's browser with javascript. From there I'd just use a switch statement or something to display the messages for browsers that aren't tested yet. If you want the exact browser version you'll have to parse it from the "navigator.userAgent" field.
If the goal is full validation, you need to be even more specific about versions. Keep in mind that some browser upgrades are not 100% backwards compatible with previous versions. (Look at how IE8 mode in IE9 is not the same as native IE8 rendering, for instance.) You're going to have to retest with every new browser version, and sooner or later there's going to be a "Fully tested with browser version X, not tested with version X+1 that was released yesterday" problem. Feature detection, graceful degradation, and a warning non-intrusively displayed to the user if their experience is being significantly downgraded is a better way to go.
To directly answer your question, if you must implement what you are asking for just parse the user agent. This could be useful specifically watching out for a browser you know doesn't work right and warning, or as a bandaid for a badly written intranet app that is very picky about the exact browser version it will run on. For a newly developed app where you have control over the requirements, I would not recommend warning on browser version since there are better ways to do it.

Cons of using Internet Explorer's Compatibility Mode

What are cons of force a web site viewed in IE to compatible mode? Say we force IE9 to IE8 compatiblity mode?
Performance drawbacks
Can't use any new IE9 specific features like HTML5/CSS3/SVG
Why?
We run legacy web app which is developed since 2000 so it's a mess ball fighting to be compatible with Chrome, Opera, Firefox, IE6/7/8 and now we decide to add IE9 to the list. But with IE9 we run in issues with printing, "Permission deniend" JavaScript errors (probably something about cross-frame JavaScript calls) and next issues - the easy workaround is to force IE9 to behave as a IE8 and then everything works fine. But I am still not sure if it's way to go...
first our app is public site (for our clients)
You have a public website developed in 2000 and it doesn't work on modern browsers? Deprecate it or re-write it.
Don't hack your code to support modern browsers, the website is clearly poorly written and doesn't apply to standards. You can't get away with this.
The only place where you can get away with this level of incompatibility is intranet applications and even then you should simply state "it works on browser X, live with it"
You can't say that to public facing clients. I mean you can try, but have fun losing business to your competitors.
Re-develop your website to match the W3C HTML/CSS standards and the ES5 standards and it will be completely future facing (for some years).
Alas, the way the web works is that anything more then 5 years old is deprecated. So either re-write it every 5 years or get out of the web business.
In terms of actually using compatibility mode, don't. IE6-8 are horrible engines and should be avoided like the plague. If you use them then you can't write future facing standards compliant code.
Your code needs to match the standards and you should fix / shim / patch any browser specific bugs where those browsers don't implement the standards.
You cannot say you have tested in IE6/7/8/9 until you have tested in those different versions. Emulating the test environment is not the same as using the test environment. To my knowledge IE7/8 compatibility modes are the older render engines, not the underlying browser as a whole, bugs and all. It is closed source so you will never know.
Convert Microsoft's free to download virtual disk images for cross-browser testing to Virtualbox images and put them on a machine that just runs Virtualbox. An old machine will do, run the VMs headless and access them with remote desktop. In that way you will be able to test in all browsers without burdening your machine with MS/Spyware.
I believe your system admins can set IE to compatibility mode for all intranet traffic using the Group Policy Editor. Any site you create will from this point forward, you can add a meta tag to force IE9 to render natively and use all the newer features...
I'm having to do that on my current project using the following doctype and meta tag in my header:
<!DOCTYPE HTML >
<meta http-equiv="X-UA-Compatible" content="IE=100" />
Compatability mode is something that MS introduced to give people some chance to upgrade their applications, not for long term use. AFAIU.
If you want your application to be compatible with IE9, then you will have to change it. If you are trying to maintain IE6-9 compatibility then you have a real challenge, and you should consider whether this is really practical - in essence, you need at least 2 distinct sets of html. Is this practical for you?
IE9 compatibility mode is different form IE9 and IE8 - it draws bits from both. So you need to do a full test agaisnt the compatibility mode version, and ensure that it remains working against this.
So in answer to the question, the cons are that you are not being IE9 compatible, and there is a danger that when IE10 comes out, your code will not run against that in any mode. You are putting the effort into compatibilty testing without providing for future changes. You would do better, in the longer term, to make your code IE9 compatible. Also, the message you are giving your clients is that your code base is not going to be compatible for much longer. Unless you are talking to them about a re-work, this is a real negative.
However, it sounds like your entire code needs a re-work, to forget about IE6 and be written for modern working browsers. Using compatibility mode until that happens is probably OK. If you do this - and tell your clients - then staying in compatibility mode is viable.
Using compatibility mode will NOT cause the browser to use the JavaScript engine that was present in the old version of IE.
By that I mean it will run any JavaScript code using the IE9 engine. Which was a problem for us when debugging an old product that had a problem with IE7/8.

Browser compatibility; Before or after uploading website to server?

I am on the stage where I need to make my website cross-browser compatible.
I need tips on how to get started.
I have developed my website on firefox, so it works great with firefox.
I guess I have to download a couple of versions of all major browsers now, right?
Then just test each browser one by one?
Should I do this before uploading the entire website onto a server or afterwards?
All tips and SW which makes this easier is appreciated.
BTW, it is a classifieds website using MySql, Solr, PHP, js etc...
Thanks
Cross-browser compatibility is best planned for in advance, as there are ways to build your site that will make it much easier.
Consider using a CSS reset script like Eric Meyer's.
Consider using a JavaScript library like jQuery.
You can make use of Adobe BrowserLab to do cross-browser testing.
Consider the mobile audience.
You need to have some kind of local webserver so you can edit the code and test it in a comfortable way. It is also helpful if you make it accessible for validator.w3.org so you can do syntax checking.
Testing it in IE6, 7 and 8, Firefox and Chrome would be a good start I would say.
Since you are working with server side code, you need to have a server.
Once the site goes live you will need both a live and a development server.
Yes, I'd make it cross browser compatible before uploading to the server. The reason for this is that you may need to change the server-side code, adding ids and classes to the markup, plus it may well be necessary to change the markup. Make sure it's working locally first.
IE Tester is very useful for testing on the various IE browsers. I'd ensure that I've tested it on a Webkit browser (such as Chrome), a Gecko Browser (such as Firefox) and Opera. See this list for different browsers.

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