javascript framework， JS常用函数（方法），jQuery

//Register NameSpace for window.MSN
if(!window.MSN)
{
    window.MSN = {};
}
if(!window.MSN.SET)
{
    window.MSN.SET = {};
}
if(!window.MSN.SET.Utilities)
{
    window.MSN.Utilities = {};
}
//Check you borwse type
//IE7 &IE8 & FF etc can render hover for div tags, but can't render under IE6.0
//this function can render hover for div under IE6.0 browse
//
MSN.SET.Utilities = {
    WebBrowserType: { IE6: 'MSIE 6.0', IE7: 'MSIE 7.0', IE8: 'MSIE 8.0', Firefox: 'Mozilla', Unknow: 'unknow' },
    checkUserWebBrowser:function(){
         var userAgent = window.navigator.userAgent;
        
         if(userAgent.indexOf(MSN.SET.Utilities.WebBrowserType.IE8) > -1) {
             return MSN.SET.Utilities.WebBrowserType.IE8;
         }
        
         if(userAgent.indexOf(MSN.SET.Utilities.WebBrowserType.IE7) > -1) {
             return MSN.SET.Utilities.WebBrowserType.IE7;
         }
        
         if(userAgent.indexOf(MSN.SET.Utilities.WebBrowserType.IE6) > -1){
             return MSN.SET.Utilities.WebBrowserType.IE6;
         }
        
         if (userAgent.indexOf(MSN.SET.Utilities.WebBrowserType.Firefox) > -1) {
            return