js转换 Fri Sep 16 00:00:00 UTC+0800 2011 格式时间函数

function Todate(num)  
{

        //Fri Oct 31 18:00:00 UTC+0800 2008  
        num=num+"";
        var date="";
        var month=new Array();
        month["Jan"]=1;month["Feb"]=2;month["Mar"]=3;month["Apr"]=4;month["May"]=5;month["Jan"]=6;
        month["Jul"]=7;month["Aug"]=8;month["Sep"]=9;month["Oct"]=10;month["Nov"]=11;month["Dec"]=12;
        var week=new Array();
        week["Mon"]="一";week["Tue"]="二";week["Wed"]="三";week["Thu"]="四";week["Fri"]="五";week["Sat"]="六";week["Sun"]="日";
        str=num.split(" ");
        date=str[5]+"-";
        date=date+month[str[1]]+"-"+str[2]+" "+str[3];
        //date=date+" 周"+week[str[0]];
        return date;
}