JavaScript 页面编码与浏览器类型判断代码

function getPageCharset(){
var charSet = "";
var oType = getBrowser();
switch(oType){
case "IE":
charSet = document.charset;
break;
case "FIREFOX":
charSet = document.characterSet;
break;
default:
break;
}
return charSet;
}

function getBrowser(){
var oType = "";
if(navigator.userAgent.indexOf("MSIE")!=-1){
oType="IE";
}else if(navigator.userAgent.indexOf("Firefox")!=-1){
oType="FIREFOX";
}
return oType;
}