javascript 之 select下拉框

javascript 之 select下拉框

1.动态创建select
    function createSelect(){
        var mySelect = document.createElement(select);
        mySelect.id = mySelect; 
        document.body.appendChild(mySelect);
    }

2.添加选项option
   function addOption(){
        根据id查找对象，
         var obj=document.getElementById('mySelect');
         添加一个选项
         obj.add(new Option(文本,值));  
   }

3.删除所有选项option
   function removeAll(){
         var obj=document.getElementById('mySelect');
         obj.options.length=0; 

   }

4.删除一个选项option
function removeOne(){
         var obj=document.getElementById('mySelect');
         var index=obj.selectedIndex;//index,要删除选项的序号，这里取当前选中选项的序号
         obj.options.remove(index); 
   }

5.获得选项option的值
var obj=document.getElementById('mySelect');
var index=obj.selectedIndex; 序号，取当前选中选项的序号
var val = obj.options[index].value;

6.获得选项option的文本
var obj=document.getElementById('mySelect');
var index=obj.selectedIndex; 序号，取当前选中选项的序号
var val = obj.options[index].text;

7.修改选项option
var obj=document.getElementById('mySelect');
var index=obj.selectedIndex; 序号，取当前选中选项的序号
var val = obj.options[index]=new Option(新文本,新值);

8.删除select
    function removeSelect(){
          var mySelect = document.getElementById(mySelect);
         mySelect.parentNode.removeChild(mySelect);
   }
转自：http://www.cnblogs.com/rayking/archive/2008/09/03/1282473.html