浏览器侦测代码 --- Browser detect

http://www.quirksmode.org/js/detect.html

var BrowserDetect = {
	init: function () {
		this.browser = this.searchString(this.dataBrowser) || "";
		this.version = this.searchVersion(navigator.userAgent) ||
			this.searchVersion(navigator.appVersion) ||
			"";
		this.OS = this.searchString(this.dataOS) || "";
	},
	searchString: function (data) {
		for (var i = 0, l = data.length ; i < l; i++){
			var dataString = data[i].string;
			var dataProp = data[i].prop;
			this.versionSearchString = data[i].versionSearch || data[i].identity;
			if (dataString) {
				if (dataString.indexOf(data[i].subString) != -1) {
					return data[i].identity;
				}
			} else if (dataProp) {
				return data[i].identity;
			}
		}
		return null;
	},
	searchVersion: function (dataString) {
		var index = dataString.indexOf(this.versionSearchString);
		if (index == -1) { return null; }
		return parseFloat(dataString.substring(index+this.versionSearchString.length+1));
	},
	dataBrowser: [
		{ string: navigator.userAgent, subString: "Chrome", identity: "Chrome" },
		{ string: navigator.userAgent, subString: "OmniWeb", versionSearch: "OmniWeb/", identity: "OmniWeb" },
		{ string: navigator.vendor, subString: "Apple", identity: "Safari", versionSearch: "Version" },
		{ prop: window.opera, identity: "Opera" },
		{ string: navigator.vendor, subString: "iCab", identity: "iCab" },
		{ string: navigator.vendor, subString: "KDE", identity: "Konqueror" },
		{ string: navigator.userAgent, subString: "Firefox", identity: "Firefox" },
		{ string: navigator.vendor, subString: "Camino", identity: "Camino" },
		{ string: navigator.userAgent, subString: "Netscape", identity: "Netscape"},
		{ string: navigator.userAgent, subString: "MSIE", identity: "Explorer", versionSearch: "MSIE" },
		{ string: navigator.userAgent, subString: "Gecko", identity: "Mozilla", versionSearch: "rv" },
		{ string: navigator.userAgent, subString: "Mozilla", identity: "Netscape", versionSearch: "Mozilla" }
	],
	dataOS : [
		{ string: navigator.platform, subString: "Win", identity: "Windows" },
		{ string: navigator.platform, subString: "Mac", identity: "Mac" },
		{ string: navigator.userAgent, subString: "iPhone", identity: "iPhone/iPod" },
		{ string: navigator.platform, subString: "Linux", identity: "Linux" }
	]

};
BrowserDetect.init();