js 输出 select 的值

    var slist = document.getElementsByTagName('select');
    for(i=0;i<slist.length;i++)
    {
        var t = slist[i].childNodes;
        for(j=0;j<t.length;j++){
            debugger;
            var z =t[j].innerHTML;
            console.log(z);
        }
        //console.log(slist[i]);
    }