Browser Detection

browser.js

var Browser = {
	type: null,
	version: null,
	support: function(obj) {
		return obj != undefined;
	},
	is: function(type, version) {
		if(type !== Browser.type) {
			return false;
		}
		if(typeof version !== 'undefined') {
			if(version === '') {
				return false;
			}
			var exp;
			if(/^[\d.]+$/.test(version)) {
				if(/^\d+$/.test(version)) {
					exp = /^(\d+)\./.exec(Browser.version);
					if(exp) {
						if(version !== exp[1]) {
							return false;
						}
					}
				}
				else if(version !== Browser.version) {
					return false;
				}
			}
			else if(/^<\d+$/.test(version)) {
				exp = /^<(\d+)$/.exec(version);
				version = parseInt(exp[1]);
				exp = /^(\d+)\./.exec(Browser.version);
				if(exp) {
					if(!(version > parseInt(exp[1]))) {
						return false;
					}
				}
			}
			else if(/^>\d+$/.test(version)) {
				exp = /^>(\d+)$/.exec(version);
				version = parseInt(exp[1]);
				exp = /^(\d+)\./.exec(Browser.version);
				if(exp) {
					if(version >= parseInt(exp[1])) {
						return false;
					}
				}
			}
			else if(/^\d+\-\d+$/.test(version)) {
				exp = /^(\d+)\-(\d+)$/.exec(version);
				var version1 = parseInt(exp[1]);
				var version2 = parseInt(exp[2]);
				exp = /^(\d+)\./.exec(Browser.version);
				if(exp) {
					if(!(version1 <= parseInt(exp[1]) && version2 >= parseInt(exp[1]))) {
						return false;
					}
				}
			}
			else {
				return false;
			}
		}
		return true;
	},
	TYPES: {
		CHROME: 'Chrome',
		FIREFOX: 'Firefox',
		IE: 'Internet Explorer',
		EDGE: 'Microsoft Edge',
	}
};

(function() {
	var types = {};
	types.chrome = !!window.chrome;
	types.firefox = typeof InstallTrigger !== 'undefined';
	types.ie = false || !!document.documentMode;
	types.edge = !types.ie && !!window.StyleMedia;
	var agent = navigator.userAgent;
	if(types.chrome) {
		Browser.type = Browser.TYPES.CHROME;
		var exp = /Chrome\/([\d.]+)/.exec(agent);
		if(exp) {
			Browser.version = exp[1];
		}
	}
	if(types.firefox) {
			Browser.type = Browser.TYPES.FIREFOX;
		var exp = /Firefox\/([\d.]+)/.exec(agent);
		if(exp) {
			Browser.version = exp[1];
		}
	}
	if(types.ie) {
		Browser.type = Browser.TYPES.IE;
		var exp = /MSIE ([\d.]+)|rv:([\d.]+)/.exec(agent);
		if(exp) {
			if(exp[1]) {
				if(exp[1] === '7.0') {
					Browser.version = "5.0-7.0";
				}
				else {
					Browser.version = exp[1];
				}
			}
			else {
				Browser.version = exp[2];
			}
		}
	}
	if(types.edge) {
		Browser.type = Browser.TYPES.EDGE;
		var exp = /Edge\/([\d.]+)/.exec(agent);
		if(exp) {
			Browser.version = exp[1];
		}
	}
})();