1 var select= document.getElementById("selectid");2 var objOption = document.createElement("OPTION");3 objOption.value = value;4 objOption.text =text;5 select.add(objOption);

 获取select选中值

var index=document.getElementById("selectid").selectedIndex;var text=document.getElementById("selectid").options[index].text;var val=document.getElementById("selectid").options[index].value;