判断浏览器类型 javascript

function getbrowser() {
var OsObject = "";
if (navigator.userAgent.indexOf("MSIE") > 0) {
return "MSIE";
}
if (isFirefox = navigator.userAgent.indexOf("Firefox") > 0) {
return "Firefox";
}
if (isSafari = navigator.userAgent.indexOf("Safari") > 0) {
return "Safari";
}
if (isCamino = navigator.userAgent.indexOf("Camino") > 0) {
return "Camino";
}
if (isMozilla = navigator.userAgent.indexOf("Gecko/") > 0) {
return "Gecko";
}
}