function addOption(objSelectNow,txt,val){
    /// 使用W3C标准语法为SELECT添加Option
    var objOption = document.createElement("OPTION");
    objOption.text=txt;
    objOption.value=val;
    objSelectNow.options.add(objOption);
}

function addOptionGroup(selectId,optGroupString){
    var optGroup = optGroupString.split(",");
    var objSelect = document.getElementsByTagName("SELECT");
    var objSelectNow = objSelect[selectId];
    objSelectNow.length = 1;
    /// 成组添加Options
    for(i=1; i<optGroup.length; i++){
        addOption(objSelectNow, optGroup[i], i);
    }
}