数据统计和降级实现基础之一，格式化UserAgent。
代码源自KISSY v1.4.x - seed.js 文件中的UA模块，并稍加修改。
var UA = (function (undefined) {
/*global process*/
var win = window,
doc = win.document,
navigator = win.navigator,
ua = navigator && navigator.userAgent || '';
function numberify(s) {
var c = 0;
// convert '1.2.3.4' to 1.234
return parseFloat(s.replace(/\./g, function () {
return (c++ === 0) ? '.' : '';
}));
}
function setTridentVersion(ua, UA) {
var core, m;
UA[core = 'trident'] = 0.1; // Trident detected, look for revision
// Get the Trident's accurate version
if ((m = ua.match(/Trident\/([\d.]*)/)) && m[1]) {
UA[core] = numberify(m[1]);
}
UA.core = core;
}
function getIEVersion(ua) {
var m, v;
if ((m = ua.match(/MSIE ([^;]*)|Trident.*; rv(?:\s|:)?([0-9.]+)/)) &&
(v = (m[1] || m[2]))) {
return numberify(v);
}
return 0;
}
function getDescriptorFromUserAgent(ua) {
var EMPTY = '',
os,
core = EMPTY,
shell = EMPTY, m,
IE_DETECT_RANGE = [6, 9],
ieVersion,
v,
end,
VERSION_PLACEHOLDER = '{{version}}',
IE_DETECT_TPL = '<!--[if IE ' + VERSION_PLACEHOLDER + ']><' + 's></s><![endif]-->',
div = doc && doc.createElement('div'),
s = [];
/**
* KISSY UA
* @class KISSY.UA
* @singleton
*/
var UA = {
/**
* webkit version
* @type undefined|Number
* @member KISSY.UA
*/
webkit : undefined,
/**
* trident version
* @type undefined|Number
* @member KISSY.UA
*/
trident: undefined,
/**
* gecko version
* @type undefined|Number
* @member KISSY.UA
*/
gecko : undefined,
/**
* presto version
* @type undefined|Number
* @member KISSY.UA
*/
presto : undefined,
/**
* chrome version
* @type undefined|Number
* @member KISSY.UA
*/
chrome : undefined,
/**
* safari version
* @type undefined|Number
* @member KISSY.UA
*/
safari : undefined,
/**
* firefox version
* @type undefined|Number
* @member KISSY.UA
*/
firefox: undefined,
/**
* ie version
* @type undefined|Number
* @member KISSY.UA
*/
ie : undefined,
/**
* ie document mode
* @type undefined|Number
* @member KISSY.UA
*/
ieMode : undefined,
/**
* opera version
* @type undefined|Number
* @member KISSY.UA
*/
opera : undefined,
/**
* mobile browser. apple, android.
* @type String
* @member KISSY.UA
*/
mobile : undefined,
/**
* browser render engine name. webkit, trident
* @type String
* @member KISSY.UA
*/
core : undefined,
/**
* browser shell name. ie, chrome, firefox
* @type String
* @member KISSY.UA
*/
shell : undefined,
/**
* PhantomJS version number
* @type undefined|Number
* @member KISSY.UA
*/
phantomjs: undefined,
/**
* operating system. android, ios, linux, windows
* @type string
* @member KISSY.UA
*/
os: undefined,
/**
* ipad ios version
* @type Number
* @member KISSY.UA
*/
ipad : undefined,
/**
* iphone ios version
* @type Number
* @member KISSY.UA
*/
iphone: undefined,
/**
* ipod ios
* @type Number
* @member KISSY.UA
*/
ipod : undefined,
/**
* ios version
* @type Number
* @member KISSY.UA
*/
ios : undefined,
/**
* android version
* @type Number
* @member KISSY.UA
*/
android: undefined,
/**
* nodejs version
* @type Number
* @member KISSY.UA
*/
nodejs: undefined
};
// ejecta
if (div && div.getElementsByTagName) {
// try to use IE-Conditional-Comment detect IE more accurately
// IE10 doesn't support this method, @ref: http://blogs.msdn.com/b/ie/archive/2011/07/06/html5-parsing-in-ie10.aspx
div.innerHTML = IE_DETECT_TPL.replace(VERSION_PLACEHOLDER, '');
s = div.getElementsByTagName('s');
}
if (s.length > 0) {
setTridentVersion(ua, UA);
// Detect the accurate version
// 注意：
// UA.shell = ie, 表示外壳是 ie
// 但 UA.ie = 7, 并不代表外壳是 ie7, 还有可能是 ie8 的兼容模式
// 对于 ie8 的兼容模式，还要通过 documentMode 去判断。但此处不能让 UA.ie = 8, 否则
// 很多脚本判断会失误。因为 ie8 的兼容模式表现行为和 ie7 相同，而不是和 ie8 相同
for (v = IE_DETECT_RANGE[0], end = IE_DETECT_RANGE[1]; v <= end; v++) {
div.innerHTML = IE_DETECT_TPL.replace(VERSION_PLACEHOLDER, v);
if (s.length > 0) {
UA[shell = 'ie'] = v;
break;
}
}
// https://github.com/kissyteam/kissy/issues/321
// win8 embed app
if (!UA.ie && (ieVersion = getIEVersion(ua))) {
UA[shell = 'ie'] = ieVersion;
}
} else {
// WebKit
if ((m = ua.match(/AppleWebKit\/([\d.]*)/)) && m[1]) {
UA[core = 'webkit'] = numberify(m[1]);
if ((m = ua.match(/OPR\/(\d+\.\d+)/)) && m[1]) {
UA[shell = 'opera'] = numberify(m[1]);
}
// Chrome
else if ((m = ua.match(/Chrome\/([\d.]*)/)) && m[1]) {
UA[shell = 'chrome'] = numberify(m[1]);
}
// Safari
else if ((m = ua.match(/\/([\d.]*) Safari/)) && m[1]) {
UA[shell = 'safari'] = numberify(m[1]);
}
// Apple Mobile
if (/ Mobile\//.test(ua) && ua.match(/iPad|iPod|iPhone/)) {
UA.mobile = 'apple'; // iPad, iPhone or iPod Touch
m = ua.match(/OS ([^\s]*)/);
if (m && m[1]) {
UA.ios = numberify(m[1].replace('_', '.'));
}
os = 'ios';
m = ua.match(/iPad|iPod|iPhone/);
if (m && m[0]) {
UA[m[0].toLowerCase()] = UA.ios;
}
} else if (/ Android/i.test(ua)) {
if (/Mobile/.test(ua)) {
os = UA.mobile = 'android';
}
m = ua.match(/Android ([^\s]*);/);
if (m && m[1]) {
UA.android = numberify(m[1]);
}
}
// Other WebKit Mobile Browsers
else if ((m = ua.match(/NokiaN[^\/]*|Android \d\.\d|webOS\/\d\.\d/))) {
UA.mobile = m[0].toLowerCase(); // Nokia N-series, Android, webOS, ex: NokiaN95
}
if ((m = ua.match(/PhantomJS\/([^\s]*)/)) && m[1]) {
UA.phantomjs = numberify(m[1]);
}
}
// NOT WebKit
else {
// Presto
// ref: http://www.useragentstring.com/pages/useragentstring.php
if ((m = ua.match(/Presto\/([\d.]*)/)) && m[1]) {
UA[core = 'presto'] = numberify(m[1]);
// Opera
if ((m = ua.match(/Opera\/([\d.]*)/)) && m[1]) {
UA[shell = 'opera'] = numberify(m[1]); // Opera detected, look for revision
if ((m = ua.match(/Opera\/.* Version\/([\d.]*)/)) && m[1]) {
UA[shell] = numberify(m[1]);
}
// Opera Mini
if ((m = ua.match(/Opera Mini[^;]*/)) && m) {
UA.mobile = m[0].toLowerCase(); // ex: Opera Mini/2.0.4509/1316
}
// Opera Mobile
// ex: Opera/9.80 (Windows NT 6.1; Opera Mobi/49; U; en) Presto/2.4.18 Version/10.00
// issue: 由于 Opera Mobile 有 Version/ 字段，可能会与 Opera 混淆，同时对于 Opera Mobile 的版本号也比较混乱
else if ((m = ua.match(/Opera Mobi[^;]*/)) && m) {
UA.mobile = m[0];
}
}
// NOT WebKit or Presto
} else {
// MSIE
// 由于最开始已经使用了 IE 条件注释判断，因此落到这里的唯一可能性只有 IE10+
// and analysis tools in nodejs
if ((ieVersion = getIEVersion(ua))) {
UA[shell = 'ie'] = ieVersion;
setTridentVersion(ua, UA);
// NOT WebKit, Presto or IE
} else {
// Gecko
if ((m = ua.match(/Gecko/))) {
UA[core = 'gecko'] = 0.1; // Gecko detected, look for revision
if ((m = ua.match(/rv:([\d.]*)/)) && m[1]) {
UA[core] = numberify(m[1]);
if (/Mobile|Tablet/.test(ua)) {
UA.mobile = 'firefox';
}
}
// Firefox
if ((m = ua.match(/Firefox\/([\d.]*)/)) && m[1]) {
UA[shell = 'firefox'] = numberify(m[1]);
}
}
}
}
}
}
if (!os) {
if ((/windows|win32/i).test(ua)) {
os = 'windows';
} else if ((/macintosh|mac_powerpc/i).test(ua)) {
os = 'macintosh';
} else if ((/linux/i).test(ua)) {
os = 'linux';
} else if ((/rhino/i).test(ua)) {
os = 'rhino';
}
}
UA.os = os;
UA.core = UA.core || core;
UA.shell = shell;
UA.ieMode = UA.ie && doc.documentMode || UA.ie;
return UA;
}
var UA = getDescriptorFromUserAgent(ua);
// nodejs
if (typeof process === 'object') {
var versions, nodeVersion;
if ((versions = process.versions) && (nodeVersion = versions.node)) {
UA.os = process.platform;
UA.nodejs = numberify(nodeVersion);
}
}
// use by analysis tools in nodejs
UA.getDescriptorFromUserAgent = getDescriptorFromUserAgent;
var browsers = [
// browser core type
'webkit',
'trident',
'gecko',
'presto',
// browser type
'chrome',
'safari',
'firefox',
'ie',
'opera'
],
documentElement = doc && doc.documentElement,
className = '';
var RE_TRIM = /^[\s\xa0]+|[\s\xa0]+$/g,
EMPTY = '';
/**
* Removes the whitespace from the beginning and end of a string.
* @method
* @member KISSY
*/
if (String.prototype.trim) {
function trim(str) {
return str == null ? EMPTY : String.prototype.trim.call(str);
}
} else {
function trim(str) {
return str == null ? EMPTY : (str + '').replace(RE_TRIM, EMPTY);
}
}
if (documentElement) {
for (var key = 0, j = browsers.length; key < j; key++) {
var v = UA[key];
if (v) {
className += ' ks-' + key + (parseInt(v) + '');
className += ' ks-' + key;
}
}
if (trim(className)) {
documentElement.className = trim(documentElement.className + className);
}
}
for (var prop in UA) {
if (!UA[prop]) {
delete UA[prop];
}
}
delete UA['getDescriptorFromUserAgent'];
return UA;
})();
/*
NOTES:
2013.07.08 yiminghe@gmail.com
- support ie11 and opera(using blink)
2013.01.17 yiminghe@gmail.com
- expose getDescriptorFromUserAgent for analysis tool in nodejs
2012.11.27 yiminghe@gmail.com
- moved to seed for conditional loading and better code share
2012.11.21 yiminghe@gmail.com
- touch and os support
2011.11.08 gonghaocn@gmail.com
- ie < 10 使用条件注释判断内核，更精确
2010.03
- jQuery, YUI 等类库都推荐用特性探测替代浏览器嗅探。特性探测的好处是能自动适应未来设备和未知设备，比如
if(document.addEventListener) 假设 IE9 支持标准事件，则代码不用修改，就自适应了“未来浏览器”。
对于未知浏览器也是如此。但是，这并不意味着浏览器嗅探就得彻底抛弃。当代码很明确就是针对已知特定浏览器的，
同时并非是某个特性探测可以解决时，用浏览器嗅探反而能带来代码的简洁，同时也也不会有什么后患。总之，一切
皆权衡。
- UA.ie && UA.ie < 8 并不意味着浏览器就不是 IE8, 有可能是 IE8 的兼容模式。进一步的判断需要使用 documentMode.
*/
附送压缩版本。
var UA=function(d){function f(b){var d=0;return parseFloat(b.replace(/\./g,function(){return 0===d++?".":""}))}function q(b,d){var e;d.trident=.1;(e=b.match(/Trident\/([\d.]*)/))&&e[1]&&(d.trident=f(e[1]));d.core="trident"}function r(b){var d,e;return(d=b.match(/MSIE ([^;]*)|Trident.*; rv(?:\s|:)?([0-9.]+)/))&&(e=d[1]||d[2])?f(e):0}function t(b){var e,g="",k="",a,h=[6,9],l,p=n&&n.createElement("div"),m=[],c={webkit:d,trident:d,gecko:d,presto:d,chrome:d,safari:d,firefox:d,ie:d,ieMode:d,opera:d,mobile:d,
core:d,shell:d,phantomjs:d,os:d,ipad:d,iphone:d,ipod:d,ios:d,android:d,nodejs:d};p&&p.getElementsByTagName&&(p.innerHTML="\x3c!--[if IE {{version}}]><s></s><![endif]--\x3e".replace("{{version}}",""),m=p.getElementsByTagName("s"));if(0<m.length){q(b,c);a=h[0];for(h=h[1];a<=h;a++)if(p.innerHTML="\x3c!--[if IE {{version}}]><s></s><![endif]--\x3e".replace("{{version}}",a),0<m.length){c[k="ie"]=a;break}!c.ie&&(l=r(b))&&(c[k="ie"]=l)}else if((a=b.match(/AppleWebKit\/([\d.]*)/))&&a[1]){c[g="webkit"]=f(a[1]);
(a=b.match(/OPR\/(\d+\.\d+)/))&&a[1]?c[k="opera"]=f(a[1]):(a=b.match(/Chrome\/([\d.]*)/))&&a[1]?c[k="chrome"]=f(a[1]):(a=b.match(/\/([\d.]*) Safari/))&&a[1]&&(c[k="safari"]=f(a[1]));if(/ Mobile\//.test(b)&&b.match(/iPad|iPod|iPhone/))c.mobile="apple",(a=b.match(/OS ([^\s]*)/))&&a[1]&&(c.ios=f(a[1].replace("_","."))),e="ios",(a=b.match(/iPad|iPod|iPhone/))&&a[0]&&(c[a[0].toLowerCase()]=c.ios);else if(/ Android/i.test(b))/Mobile/.test(b)&&(e=c.mobile="android"),(a=b.match(/Android ([^\s]*);/))&&a[1]&&
(c.android=f(a[1]));else if(a=b.match(/NokiaN[^\/]*|Android \d\.\d|webOS\/\d\.\d/))c.mobile=a[0].toLowerCase();(a=b.match(/PhantomJS\/([^\s]*)/))&&a[1]&&(c.phantomjs=f(a[1]))}else if((a=b.match(/Presto\/([\d.]*)/))&&a[1])c[g="presto"]=f(a[1]),(a=b.match(/Opera\/([\d.]*)/))&&a[1]&&(c[k="opera"]=f(a[1]),(a=b.match(/Opera\/.* Version\/([\d.]*)/))&&a[1]&&(c[k]=f(a[1])),(a=b.match(/Opera Mini[^;]*/))&&a?c.mobile=a[0].toLowerCase():(a=b.match(/Opera Mobi[^;]*/))&&a&&(c.mobile=a[0]));else if(l=r(b))c[k=
"ie"]=l,q(b,c);else if(a=b.match(/Gecko/))c[g="gecko"]=.1,(a=b.match(/rv:([\d.]*)/))&&a[1]&&(c[g]=f(a[1]),/Mobile|Tablet/.test(b)&&(c.mobile="firefox")),(a=b.match(/Firefox\/([\d.]*)/))&&a[1]&&(c[k="firefox"]=f(a[1]));e||(/windows|win32/i.test(b)?e="windows":/macintosh|mac_powerpc/i.test(b)?e="macintosh":/linux/i.test(b)?e="linux":/rhino/i.test(b)&&(e="rhino"));c.os=e;c.core=c.core||g;c.shell=k;c.ieMode=c.ie&&n.documentMode||c.ie;return c}var e=window,n=e.document,e=e.navigator,e=t(e&&e.userAgent||
"");if("object"===typeof process){var h,g;(h=process.versions)&&(g=h.node)&&(e.os=process.platform,e.nodejs=f(g))}e.getDescriptorFromUserAgent=t;var m="webkit trident gecko presto chrome safari firefox ie opera".split(" ");h=n&&n.documentElement;g="";var x=/^[\s\xa0]+|[\s\xa0]+$/g,u=String.prototype.trim?function(b){return null==b?"":String.prototype.trim.call(b)}:function(b){return null==b?"":(b+"").replace(x,"")};if(h){for(var l=0,m=m.length;l<m;l++){var v=e[l];v&&(g+=" ks-"+l+(parseInt(v)+""),
g+=" ks-"+l)}u(g)&&(h.className=u(h.className+g))}for(var w in e)e[w]||delete e[w];delete e.getDescriptorFromUserAgent;return e}();
如果想要一个基本够用的，不妨使用下面的。
var UA=function(d){function f(b){var d=0;return parseFloat(b.replace(/\./g,function(){return 0===d++?".":""}))}function p(b,d){var e;d.trident=.1;(e=b.match(/Trident\/([\d.]*)/))&&e[1]&&(d.trident=f(e[1]));d.core="trident"}function q(b){var d,e;return(d=b.match(/MSIE ([^;]*)|Trident.*; rv(?:\s|:)?([0-9.]+)/))&&(e=d[1]||d[2])?f(e):0}var e=window,r=e.document,e=e.navigator,e=function(b){var e,g="",h="",a,l=[6,9],m,k=r&&r.createElement("div"),n=[],c={webkit:d,trident:d,gecko:d,presto:d,chrome:d,safari:d,
firefox:d,ie:d,opera:d,mobile:d,core:d,shell:d,phantomjs:d,os:d,ipad:d,iphone:d,ipod:d,ios:d,android:d,nodejs:d};k&&k.getElementsByTagName&&(k.innerHTML="\x3c!--[if IE {{version}}]><s></s><![endif]--\x3e".replace("{{version}}",""),n=k.getElementsByTagName("s"));if(0<n.length){p(b,c);a=l[0];for(l=l[1];a<=l;a++)if(k.innerHTML="\x3c!--[if IE {{version}}]><s></s><![endif]--\x3e".replace("{{version}}",a),0<n.length){c[h="ie"]=a;break}!c.ie&&(m=q(b))&&(c[h="ie"]=m)}else if((a=b.match(/AppleWebKit\/([\d.]*)/))&&
a[1]){c[g="webkit"]=f(a[1]);(a=b.match(/OPR\/(\d+\.\d+)/))&&a[1]?c[h="opera"]=f(a[1]):(a=b.match(/Chrome\/([\d.]*)/))&&a[1]?c[h="chrome"]=f(a[1]):(a=b.match(/\/([\d.]*) Safari/))&&a[1]&&(c[h="safari"]=f(a[1]));if(/ Mobile\//.test(b)&&b.match(/iPad|iPod|iPhone/))c.mobile="apple",(a=b.match(/OS ([^\s]*)/))&&a[1]&&(c.ios=f(a[1].replace("_","."))),e="ios",(a=b.match(/iPad|iPod|iPhone/))&&a[0]&&(c[a[0].toLowerCase()]=c.ios);else if(/ Android/i.test(b)){if(/Mobile/.test(b)&&(e=c.mobile="android"),(a=b.match(/Android ([^\s]*);/))&&
a[1])c.android=f(a[1])}else if(a=b.match(/NokiaN[^\/]*|Android \d\.\d|webOS\/\d\.\d/))c.mobile=a[0].toLowerCase();(a=b.match(/PhantomJS\/([^\s]*)/))&&a[1]&&(c.phantomjs=f(a[1]))}else if((a=b.match(/Presto\/([\d.]*)/))&&a[1]){if(c[g="presto"]=f(a[1]),(a=b.match(/Opera\/([\d.]*)/))&&a[1])c[h="opera"]=f(a[1]),(a=b.match(/Opera\/.* Version\/([\d.]*)/))&&a[1]&&(c[h]=f(a[1])),(a=b.match(/Opera Mini[^;]*/))&&a?c.mobile=a[0].toLowerCase():(a=b.match(/Opera Mobi[^;]*/))&&a&&(c.mobile=a[0])}else if(m=q(b))c[h=
"ie"]=m,p(b,c);else if(a=b.match(/Gecko/))c[g="gecko"]=.1,(a=b.match(/rv:([\d.]*)/))&&a[1]&&(c[g]=f(a[1]),/Mobile|Tablet/.test(b)&&(c.mobile="firefox")),(a=b.match(/Firefox\/([\d.]*)/))&&a[1]&&(c[h="firefox"]=f(a[1]));e||(/windows|win32/i.test(b)?e="windows":/macintosh|mac_powerpc/i.test(b)?e="macintosh":/linux/i.test(b)?e="linux":/rhino/i.test(b)&&(e="rhino"));c.os=e;c.core=c.core||g;c.shell=h;return c}(e&&e.userAgent||"");if("object"===typeof process){var g,t;(g=process.versions)&&(t=g.node)&&(e.os=
process.platform,e.nodejs=f(t))}for(g in e)e[g]||delete e[g];return e}();console.log(UA);
关于UA，还有几篇老文，或许你会感兴趣。