检测JS中的所有Firefox版本

Question

How to detect Firefox in JavaScript?
I want to detect all versions of Firefox.

Answer 1

This will detect any version of Firefox:

var isFirefox = navigator.userAgent.toLowerCase().indexOf('firefox') > -1;

more specifically:

if(navigator.userAgent.toLowerCase().indexOf('firefox') > -1){
     // Do Firefox-related activities
}

You may want to consider using feature-detection ala Modernizr , or a related tool, to accomplish what you need.

Answer 2

If you'd like to know what is the numeric version of FireFox you can use the following snippet:

var match = window.navigator.userAgent.match(/Firefox\/([0-9]+)\./);
var ver = match ? parseInt(match[1]) : 0;

Answer 3

This script detects all versions of Firefox, for Desktop, from version 1 to 46.

It's the third time I've tried to answer this question on StackOverflow because I kept finding new ways to break my script. However, I think it's working now. It's a great exercise to learn about Firefox features and interesting to see how things have evolved. The script can be rewritten with different features, I chose ones I thought would be most useful, I would love for someone else to rewrite with other more useful features and post here, and compare results.

I placed the script in a try statement in case the user has any disabled settings in about.config. Otherwise I tested on every version of Firefox and it detects each one. I gave a brief description of what each feature is used for in the comments. I would like to do this for Webkit too but find the documentation not as good. Mozilla has easy to download previous versions and detailed releases.

 // Element to display version var outputVersion = document.getElementById("displayFoxVersion"); try { // Match UserAgent string with Firefox Desktop // Detect hybrid Gecko browsers and mobile if (navigator.userAgent.match(/firefox/i) && !navigator.userAgent.match(/mobi|tablet|fennec|android|netscape|seamonkey|iceweasel|iceape|icecat|waterfox|gnuzilla|shadowfox|swiftfox/i)) { // Create Element and Array to test availability var createdElement = document.createElement('div'), createdArray = [], firefoxVersion = "0"; // Firefox 1.0 released November 9, 2004 // Check a current feature as being true, or NOT undefined // AND check future features as EQUAL undefined if (typeof window.alert !== "undefined" && typeof window.XPCNativeWrapper === "undefined" && typeof window.URL === "undefined") { firefoxVersion = "1"; } // Firefox 1.5 released October 15, 2003 // XPCNativeWrapper used to create security wrapper else if (typeof window.XPCNativeWrapper !== "undefined" && typeof window.globalStorage === "undefined" && typeof window.devicePixelRatio === "undefined" && typeof createdElement.style.animation === "undefined" && typeof document.querySelector === "undefined") { firefoxVersion = "1.5"; } // Firefox 2 released October 24, 2006 // globalStorage later deprecated in favor of localstorage else if (typeof window.globalStorage !== "undefined" && typeof window.postMessage === "undefined") { firefoxVersion = "2"; } // Firefox 3 released June 17, 2008 // postMessage for cross window messaging else if (typeof window.postMessage !== "undefined" && typeof document.querySelector === "undefined") { firefoxVersion = "3"; } // Firefox 3.5 released June 30, 2009 // querySelector returns list of the elements from document else if (typeof document.querySelector !== "undefined" && typeof window.mozRequestAnimationFrame === "undefined" && typeof Reflect === "undefined") { firefoxVersion = "3.5"; } // Firefox 4 released March 22, 2011 // window.URL is Gecko, Webkit is window.webkitURL, manages object URLs else if (typeof window.URL !== "undefined" && typeof createdElement.style.MozAnimation === "undefined") { firefoxVersion = "4"; } // After April 2011 releases every six weeks on Tuesday // Firefox 5 released June 21, 2011 // style.MozAnimation for CSS animation, renamed to style.animation else if (typeof createdElement.style.MozAnimation !== "undefined" && typeof WeakMap === "undefined") { firefoxVersion = "5"; } // Firefox 6 released August 16, 2011 // WeakMap collects key value pairs weakly referenced else if (typeof WeakMap !== "undefined" && typeof createdElement.style.textOverflow === "undefined") { firefoxVersion = "6"; } // Firefox 7 released September 27, 2011 // textOverflow manages overflowed non displayed content else if (typeof createdElement.style.textOverflow !== "undefined" && typeof createdElement.insertAdjacentHTML === "undefined") { firefoxVersion = "7"; } // Firefox 8 released November 8, 2011 // insertAdjacentHTML parses as HTML and inserts into specified position // faster than direct innerHTML manipulation and // appends without affecting other elements under the same parent else if (typeof createdElement.insertAdjacentHTML !== "undefined" && typeof navigator.doNotTrack === "undefined") { firefoxVersion = "8"; } // Firefox 9 released December 20, 2011 // mozIndexedDB dropped ver 16, renamed window.indexedDB // IndexDB improved functionality than localstorage else if (typeof window.mozIndexedDB !== "undefined" && typeof document.mozFullScreenEnabled === "undefined") { firefoxVersion = "9"; } // Firefox 10 released January 31, 2012 // mozFullScreenEnabled reports if full-screen mode is available else if (typeof document.mozFullScreenEnabled !== "undefined" && typeof window.mozCancelAnimationFrame === "undefined" && typeof Reflect === "undefined") { firefoxVersion = "10"; } // Firefox 11 released March 13, 2012 // mozCancelAnimationFrame prior to Firefox 23 prefixed with moz // Cancels an animation frame request else if (typeof window.mozCancelAnimationFrame !== "undefined" && typeof createdElement.style.MozTextAlignLast === "undefined") { firefoxVersion = "11"; } // Firefox 12 released April 24, 2012 // MozTextAlignLast how the last line is aligned else if (typeof createdElement.style.MozTextAlignLast !== "undefined" && typeof createdElement.style.MozOpacity !== "undefined") { firefoxVersion = "12"; } // Firefox 13 released June 5, 2012 // MozOpacity dropped from this version else if (typeof createdElement.style.MozOpacity === "undefined" && typeof window.globalStorage !== "undefined") { firefoxVersion = "13"; } // Firefox 14 released June 26, 2012 // globalStorage dropped from this version else if (typeof window.globalStorage === "undefined" && typeof createdElement.style.borderImage === "undefined" && typeof document.querySelector !== "undefined") { firefoxVersion = "14"; } // Firefox 15 released August 28, 2012 // borderImage allows drawing an image on the borders of elements else if (typeof createdElement.style.borderImage !== "undefined" && typeof createdElement.style.animation === "undefined") { firefoxVersion = "15"; } // Firefox 16 released October 9, 2012 // animation was MozAnimation else if (typeof createdElement.style.animation !== "undefined" && typeof createdElement.style.iterator === "undefined" && typeof Math.hypot === "undefined") { firefoxVersion = "16"; } // Firefox 17 released November 20, 2012 // version 27 drops iterator and renames italic // Used to iterate over enumerable properties of an object else if (typeof createdElement.style.iterator !== "undefined" && typeof window.devicePixelRatio === "undefined") { firefoxVersion = "17"; } // Firefox 18 released January 8, 2013 // devicePixelRatio returns ratio of one vertical pixel between devices else if (typeof window.devicePixelRatio !== "undefined" && typeof window.getInterface === "undefined" && typeof createdElement.style.mixBlendMode === "undefined") { firefoxVersion = "18"; } // Firefox 19 released February 19, 2013 // getInterface dropped and renamed in version 32 // Retrieves specified interface pointers else if (typeof window.getInterface !== "undefined" && typeof Math.imul === "undefined") { firefoxVersion = "19"; } // Firefox 20 released April 2, 2013 // Math.imul provides fast 32 bit integer multiplication else if (typeof Math.imul !== "undefined" && typeof window.crypto.getRandomValues === "undefined") { firefoxVersion = "20"; } // Firefox 21 released May 14, 2013 // getRandomValues lets you get cryptographically random values else if (typeof window.crypto.getRandomValues !== "undefined" && typeof createdElement.style.flex === "undefined") { firefoxVersion = "21"; } // Firefox 22 released June 25, 2013 // flex can alter dimensions to fill available space else if (typeof createdElement.style.flex !== "undefined" && typeof window.cancelAnimationFrame === "undefined") { firefoxVersion = "22"; } // Firefox 23 released August 6, 2013 // cancelAnimationFrame was mozCancelAnimationFrame else if (typeof window.cancelAnimationFrame !== "undefined" && typeof document.loadBindingDocument !== "undefined" && typeof Math.trunc === "undefined") { firefoxVersion = "23"; } // Firefox 24 released September 17, 2013 // loadBindingDocument dropped // loadBindingDocument reintroduced in 25 then dropped again in 26 else if (typeof document.loadBindingDocument === "undefined" && typeof Math.trunc === "undefined") { firefoxVersion = "24"; } // Firefox 25 released October 29, 2013 // Math.trunc returns number removing fractional digits else if (typeof Math.trunc !== "undefined" && typeof document.loadBindingDocument !== "undefined") { firefoxVersion = "25"; } // Firefox 26 released December 10, 2013 // loadBindingDocument dropped else if (typeof Math.trunc !== "undefined" && typeof Math.hypot === "undefined") { firefoxVersion = "26"; } // Firefox 27 released February 4, 2014 // Math.hypot returns square root of the sum of squares else if (typeof Math.hypot !== "undefined" && typeof createdArray.entries === "undefined") { firefoxVersion = "27"; } // Firefox 28 released March 18, 2014 // entries returns key value pairs for arrays else if (typeof createdArray.entries !== "undefined" && typeof createdElement.style.boxSizing === "undefined") { firefoxVersion = "28"; } // Firefox 29 released April 29, 2014 // boxSizing alters CSS box model, calculates width and height of elements else if (typeof createdElement.style.boxSizing != "undefined" && typeof createdElement.style.backgroundBlendMode === "undefined") { firefoxVersion = "29"; } // Firefox 30 released June 10, 2014 // backgroundBlendMode blends elements background images else if (typeof createdElement.style.backgroundBlendMode !== "undefined" && typeof createdElement.style.paintOrder === "undefined") { firefoxVersion = "30"; } // Firefox 31 released July 22, 2014 // paintOrder specifies the order fill, stroke, markers of shape or element else if (typeof createdElement.style.paintOrder !== "undefined" && typeof createdElement.style.mixBlendMode === "undefined") { firefoxVersion = "31"; } // Firefox 32 released September 2, 2014 // mixBlendMode how an element should blend else if (typeof createdElement.style.mixBlendMode !== "undefined" && typeof Number.toInteger !== "undefined") { firefoxVersion = "32"; } // Firefox 33 released October 14, 2014 // numberToIntger dropped, used to convert values to integer else if (typeof Number.toInteger === "undefined" && typeof createdElement.style.fontFeatureSettings === "undefined") { firefoxVersion = "33"; } // Firefox 34 released December 1, 2014 // fontFeatureSettings control over advanced typographic features else if (typeof createdElement.style.fontFeatureSettings !== "undefined" && typeof navigator.mozIsLocallyAvailable !== "undefined") { firefoxVersion = "34"; } // Firefox 35 released January 13, 2015 // mozIsLocallyAvailable dropped else if (typeof navigator.mozIsLocallyAvailable === "undefined" && typeof createdElement.style.MozWindowDragging === "undefined") { firefoxVersion = "35"; } // Firefox 36 released February 24, 2015 // quote returns a copy of the string else if (typeof String.quote !== "undefined" && typeof createdElement.style.MozWindowDragging !== "undefined") { firefoxVersion = "36"; } // Firefox 37 released March 31, 2015 // quote quickly dropped else if (typeof String.quote === "undefined" && typeof createdElement.style.rubyPosition === "undefined") { firefoxVersion = "37"; } // Firefox 38 released May 12, 2015 // rubyPosition defines position of a ruby element relative to its base element else if (typeof createdElement.style.rubyPosition !== "undefined" && typeof window.Headers === "undefined") { firefoxVersion = "38"; } // Firefox 39 released July 2, 2015 // Headers allows us to create our own headers objects else if (typeof window.Headers !== "undefined" && typeof Symbol.match === "undefined") { firefoxVersion = "39"; } // Firefox 40 released August 11, 2015 // match matches a regular expression against a string else if (typeof Symbol.match !== "undefined" && typeof Symbol.species === "undefined") { firefoxVersion = "40"; } // Firefox 41 released September 22, 2015 // species allows subclasses to over ride the default constructor else if (typeof Symbol.species !== "undefined" && typeof Reflect === "undefined") { firefoxVersion = "41"; } // Firefox 42 released November 3, 2015 // mozRequestAnimationFrame and mozFullScreenEnabled dropped // Reflect offers methods for interceptable JavaScript operations else if (typeof Reflect !== "undefined" && typeof window.screen.orientation === "undefined") { firefoxVersion = "42"; } // Firefox 43 released December 15, 2015 // orientation is mozOrientation in B2G and Android else if (typeof window.screen.orientation !== "undefined" && typeof document.charset === "undefined") { firefoxVersion = "43"; } // Firefox 44 released January 26, 2016 // charset is for legacy, use document.characterSet else if (typeof document.charset !== "undefined" && typeof window.onstorage === "undefined") { firefoxVersion = "44"; } // Firefox 45 released March 8, 2016 // onstorage contains an event handler that runs when the storage event fires else if (typeof window.onstorage !== "undefined" && typeof window.onabsolutedeviceorientation === "undefined") { firefoxVersion = "45"; } // Firefox 46 - beta // onabsolutedeviceorientation else if (typeof window.onabsolutedeviceorientation !== "undefined") { firefoxVersion = "46 or above"; } // Else could not verify else { outputVersion.innerHTML = "Could not verify Mozilla Firefox"; } // Display Firefox version outputVersion.innerHTML = "Verified as Mozilla Firefox " + firefoxVersion; // Else not detected } else { outputVersion.innerHTML = "Mozilla Firefox not detected"; } } catch (e) { // Statement to handle exceptions outputVersion.innerHTML = "An error occured. This could be because the default settings in Firefox have changed. Check about.config "; } 

 <div id="displayFoxVersion"></div> 

Answer 4

For a long time I have used the alternative:

('netscape' in window) && / rv:/.test(navigator.userAgent)

because I don't trust user agent strings. Some bugs are not detectable using feature detection, so detecting the browser is required for some workarounds.

Also if you are working around a bug in Gecko, then the bug is probably also in derivatives of Firefox, and this code should work with derivatives too (Do Waterfox and Pale Moon have 'Firefox' in the user agent string?).

Answer 5

An alternate answer:

parseFloat(navigator.userAgent.split('Firefox/').pop(), 10) >= 92;

should be faster than using regexps...

Answer 6

    <script type="text/javascript">
           var isChrome = /Chrome/.test(navigator.userAgent) && /Google 
                           Inc/.test(navigator.vendor);
           var isFirefox = 
                  navigator.userAgent.toLowerCase().indexOf('firefox') > -1;
           if (isChrome) 
           { 
               document.write('<'+'link rel="stylesheet" 
                                  href="css/chrome.css" />');

           }
          else if(isFirefox)
           {
               document.write('<'+'link rel="stylesheet" 
                                  href="css/Firefox.css" />');
           }
           else
           {
                document.write('<'+'link rel="stylesheet" 
                                   href="css/IE.css" />');
            }

     </script>

This works perfect for IE,Firefox and Chrome.

Answer 7

Detect the user agent, then check for firefox in the response:

navigator.userAgent.toLowerCase().includes('firefox') // true || false

Answer 8

here it it

var ffversion = '18';
var is_firefox = navigator.userAgent.toLowerCase().indexOf('firefox/'+ffversion) > -1;
alert(is_firefox);

Answer 9

the best solution for me:

 function GetIEVersion() { var sAgent = window.navigator.userAgent; var Idx = sAgent.indexOf("MSIE"); // If IE, return version number. if (Idx > 0) return parseInt(sAgent.substring(Idx+ 5, sAgent.indexOf(".", Idx))); // If IE 11 then look for Updated user agent string. else if (!!navigator.userAgent.match(/Trident\\/7\\./)) return 11; else return 0; //It is not IE } if (GetIEVersion() > 0){ alert("This is IE " + GetIEVersion()); }else { alert("This no is IE "); }