Browser Detect

It's like a crystal ball for user agents.

Browser Detect identifies the client browser using the user agent string that was supplied in the page request. Browser Detect searches the user agent string for any string you provide, and it also supports some special groupings and shortcuts:

• ie (Any version of IE, excluding browsers like Opera and WebTV that identify themselves as IE)
• ie{integer} (A specific major version of IE — "ie6", "ie7", "ie8", etc.)
• robot (Google bot, MSN bot, Yahoo! bot)
• ios (iPhone, iPod, iPad)
• webkit (Any WebKit based browser)
• mobile (Any modern mobile browser — iOS, Android, Palm webOS)

Using Bundler, all you need to do is add the source to your Gemfile:

gem "browser_detect"

Then run:

bundle install

or, install it as a plugin using Rails 2:

script/plugin install git://github.com/traction/browser_detect.git

To check if a particular browser made the request, use browser_is?(name)

def index if browser_is?("chrome") # load some chrome-specific content end end

or in a view:

<%= browser_is?(:chrome) ? "secrets" : "buzz off" %>

Don't forget you can use the special groupings listed above to target IE, robots, iOS, etc.

<%= stylesheet_link_tag "ugly_styles" if browser_is?('ie') %> <%= stylesheet_link_tag "even_uglier_styles" if browser_is?('ie6') %> <%= render "seo_spam_content" if browser_is?('robot') %>

There's also a convenience method browser_is_mobile? which is just a shortcut to browser_is?('mobile')

def index if browser_is_mobile? # redirect to the mobile site end end

For WebKit-based browsers, you can also check the WebKit version using browser_webkit_version. This can be useful for determining what rendering capabilities the browser has. For instance, early versions of Mobile WebKit crash intermittently when you use multiple faces or weights of web fonts. So you might prevent your web fonts from rendering on old WebKit versions:

<%= stylesheet_link_tag "fonts" unless (browser_is?('ios') and browser_webkit_version < 532) %>

See http://rdoc.info/github/traction/browser_detect/master/frames

Additions to the text fixtures (list of user agent strings for testing) are always welcome, as are new definitions of browser groupings. Please fork and submit a pull request!

Originally based on work by rlivsey. Current contributors:

• faunzy
• ggilder
• tmlee