JavaScript判断浏览器类型

	var browserName = navigator.userAgent.toLowerCase();
	if (/msie/i.test(browserName) && !/opera/.test(browserName)) {
		alert("IE");
		return;
	} else if (/firefox/i.test(browserName)) {
		alert("Firefox");
		return;
	} else if (/chrome/i.test(browserName) && /webkit/i.test(browserName) && /mozilla/i.test(browserName)) {
		alert("Chrome");
		return;
	} else if (/opera/i.test(browserName)) {
		alert("Opera");
		return;
	} else if (/webkit/i.test(browserName) && !(/chrome/i.test(browserName) && /webkit/i.test(browserName) && /mozilla/i.test(browserName))) {
		alert("Safari");
		return;
	} else {
		alert("unKnow");
	}