JSFiddle - React, Tailwind, and code Playground

by jstenkvist

JavaScript

function checkBrowser () {

	// Opera 8.0+
	var isOpera = (!!window.opr && !!opr.addons) || !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0;

	// Firefox 1.0+
	var isFirefox = typeof InstallTrigger !== 'undefined';

	// Safari 3.0+ "[object HTMLElementConstructor]" 
	var isSafari = /constructor/i.test(window.HTMLElement) || (function (p) { return p.toString() === "[object SafariRemoteNotification]"; })(!window['safari'] || (typeof safari !== 'undefined' && window['safari'].pushNotification));

	// Internet Explorer 6-11
	var isIE = /*@cc_on!@*/false || !!document.documentMode;

	// Edge 20+
	var isEdge = !isIE && !!window.StyleMedia;

	// Chrome 1 - 79
	var isChrome = !!window.chrome && (!!window.chrome.webstore || !!window.chrome.runtime);

	// Edge (based on chromium) detection
	var isEdgeChromium = isChrome && (navigator.userAgent.indexOf("Edg") != -1);

	// Blink engine detection
	var isBlink = (isChrome || isOpera) && !!window.CSS;


	var output = 'Detecting browsers by ducktyping:<hr>';
	output += 'isFirefox: ' + isFirefox + '<br>';
	output += 'isChrome: ' + isChrome + '<br>';
	output += 'isSafari: ' + isSafari + '<br>';
	output += 'isOpera: ' + isOpera + '<br>';
	output += 'isIE: ' + isIE + '<br>';
	output += 'isEdge: ' + isEdge + '<br>';
	output += 'isEdgeChromium: ' + isEdgeChromium + '<br>';
	output += 'isBlink: ' + isBlink + '<br>';
	document.body.innerHTML = output;
	
	var returnBrowser = isFirefox ? 'isFirefox' : isChrome ? 'isChrome' : isSafari ? 'isSafari' : isOpera ? 'isOpera' : isEdge ? 'isEdge' : isEdgeChromium ? 'isEdgeChromium' : isBlink ? 'isBlink' : isIE ? 'isIE' : 'Could not detect browser or browser is unknown!';
	
  return returnBrowser;
}

var ieString = 'isIE';
console.log(checkBrowser().normalize() !== ieString.normalize());
// expected output: "$2.00"