Using Javascript to detect Google Chrome to switch CSS

Question

I have been playing around with different scripts, I found one that works for everything but Chrome... this is the code I have been using to differ in .CSS files. I tried just makeing the Browser name into "Chrome" But that did not work.

if (browser == 'Firefox') {
    document.write('<link rel="stylesheet" href="../component/fireFoxdefault.css" />');
}
if (browser == 'Safari') {
    document.write('<'+'link rel="stylesheet" href="../component/default.css" />');
}

Solution 1

Use the following to detect chrome:

var isChrome = navigator.userAgent.toLowerCase().indexOf('chrome') > -1;

Source: http://davidwalsh.name/detecting-google-chrome-javascript

Update (2015-07-20):

The above solution does not always work. A more reliable solution can be found in this answer (see below). That being said, I would avoid browser detection and go with feature detection instead:

var isChrome = /Chrome/.test(navigator.userAgent) && /Google Inc/.test(navigator.vendor); 

You can include a css file specifically for chrome like this:

if (isChrome) {
    document.write('<'+'link rel="stylesheet" href="../component/chromeDefault.css" />');
}

UPDATE (2014-07-29):

@gillesc has a more elegant suggestion for detecting Chrome which he posted in a comment below and it can also be viewed on this question.

var isChrome = !!window.chrome

Solution 2

Here are two simple methods,one using indexOf and one using test :

// first method 
function check_chrome_ua() {
    var ua = navigator.userAgent.toLowerCase();
    var is_chrome = /chrome/.test(ua);

    return is_chrome;
}

// second method */
function check_chrome_ua2() {
    var ua = navigator.userAgent.toLowerCase();
    var is_chrome = ua.indexOf("applewebkit/") != -1 && ua.indexOf("khtml") > - 1;

    return is_chrome;
}

alert(check_chrome_ua()); // false or true 
alert(check_chrome_ua2()); // false or true

After checking if chrome is in use or not with one of these two boolean functions,you can implement your method on changing the stylesheet.

Solution 3

Update for Chrome on iOS: Chrome 38 (tested on iOS 8.1) returns false on !!window.chrome. To fix this you can use:

function isChrome(){
    var windowChrome = !!window.chrome;
    if(!windowChrome){
        // Chrome iOS specific test
        var pattern = /crios/i;
        return pattern.test(window.navigator.userAgent);
    }else{
        return windowChrome;
    }
}

Google reference on the matter