//多个同名的select值
var s=$("select[name=dutylistall]");
var dutylistall="";
s.each(function(i,el){
//console.info(i);
//console.info(el);
//console.info($(el).find("option:selected").val());
if(i!=0){
dutylistall+=",";
}
dutylistall += $(el).find("option:selected").val();
});