How can you detect the version of a browser?

Question

I\'ve been searching around for code that would let me detect if the user visiting the website has Firefox 3 or 4. All I have found is code to detect the type of browser but

Answer 1

I was looking for a solution for myself, since jQuery 1.9.1 and above have removed the $.browser functionality. I came up with this little function that works for me. It does need a global variable (I've called mine _browser) in order to check which browser it is. I've written a jsfiddle to illustrate how it can be used, of course it can be expanded for other browsers by just adding a test for _browser.foo, where foo is the name of the browser. I did just the popular ones.

detectBrowser()

_browser = {};

function detectBrowser() {
  var uagent = navigator.userAgent.toLowerCase(),
      match = '';

  _browser.chrome  = /webkit/.test(uagent)  && /chrome/.test(uagent)      &&
                     !/edge/.test(uagent);

  _browser.firefox = /mozilla/.test(uagent) && /firefox/.test(uagent);

  _browser.msie    = /msie/.test(uagent)    || /trident/.test(uagent)     ||
                     /edge/.test(uagent);

  _browser.safari  = /safari/.test(uagent)  && /applewebkit/.test(uagent) &&
                     !/chrome/.test(uagent);

  _browser.opr     = /mozilla/.test(uagent) && /applewebkit/.test(uagent) &&
                     /chrome/.test(uagent)  && /safari/.test(uagent)      &&
                     /opr/.test(uagent);

  _browser.version = '';

  for (x in _browser) {
    if (_browser[x]) {

      match = uagent.match(
                new RegExp("(" + (x === "msie" ? "msie|edge" : x) + ")( |\/)([0-9]+)")
              );

      if (match) {
        _browser.version = match[3];
      } else {
        match = uagent.match(new RegExp("rv:([0-9]+)"));
        _browser.version = match ? match[1] : "";
      }
      break;
    }
  }
  _browser.opera = _browser.opr;
  delete _browser.opr;
}

To check if the current browser is Opera you would do

if (_browser.opera) { // Opera specific code }

Edit Fixed the formatting, fixed the detection for IE11 and Opera/Chrome, changed to browserResult from result. Now the order of the _browser keys doesn't matter. Updated jsFiddle link.

2015/08/11 Edit Added new testcase for Internet Explorer 12 (EDGE), fixed a small regexp problem. Updated jsFiddle link.