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Yahoo! UI Library

YAHOO Global  2.6.0

Yahoo! UI Library > yahoo > YAHOO.env.ua

static Class YAHOO.env.ua

Do not fork for a browser if it can be avoided. Use feature detection when you can. Use the user agent as a last resort. YAHOO.env.ua stores a version number for the browser engine, 0 otherwise. This value may or may not map to the version number of the browser using the engine. The value is presented as a float so that it can easily be used for boolean evaluation as well as for looking for a particular range of versions. Because of this, some of the granularity of the version info may be lost (e.g., Gecko reports 1.8).


air - float

Adobe AIR version number or 0. Only populated if webkit is detected. Example: 1.0

gecko - float

Gecko engine revision number. Will evaluate to 1 if Gecko is detected but the revision could not be found. Other browsers will be 0. Example: 1.8
Firefox 1.7.8   <-- Reports 1.7
Firefox <-- Reports 1.8
Firefox <-- Reports 1.8
Firefox 3 alpha: 1.9a4   <-- Reports 1.9

ie - float

Internet Explorer version number or 0. Example: 6

mobile - string

The mobile property will be set to a string containing any relevant user agent information when a modern mobile browser is detected. Currently limited to Safari on the iPhone/iPod Touch, Nokia N-series devices with the WebKit-based browser, and Opera Mini.

opera - float

Opera version number or 0. Example: 9.2

webkit - float

AppleWebKit version. KHTML browsers that are not WebKit browsers will evaluate to 1, other browsers 0. Example: 418.9.1
Safari 1.3.2 (312.6): 312.8.1 <-- Reports 312.8 -- currently the 
latest available for Mac OSX 10.3.
Safari 2.0.2:         416     <-- hasOwnProperty introduced
Safari 2.0.4:         418     <-- preventDefault fixed
Safari 2.0.4 (419.3): 418.9.1 <-- One version of Safari may run
different versions of webkit
Safari 2.0.4 (419.3): 419     <-- Tiger installations that have been
updated, but not updated
to the latest patch.
Webkit 212 nightly:   522+    <-- Safari 3.0 precursor (with native SVG
and many major issues fixed).  
3.x yahoo.com, flickr:422     <-- Safari 3.x hacks the user agent
string when hitting yahoo.com and 
Safari 3.0.4 (523.12):523.12  <-- First Tiger release - automatic update
from 2.x via the 10.4.11 OS patch
Webkit nightly 1/2008:525+    <-- Supports DOMContentLoaded event.
yahoo.com user agent hack removed.

Copyright © 2008 Yahoo! Inc. All rights reserved.