DropDownList的相关操作

1.绑定DropDownList
public void FillCBL(DataSet ds,CheckBoxList cbl)
    {
        if (ds != null)
        {
            if (ds.Tables[0].Rows.Count > 0)
            {
                for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
                {
                    cbl.Items.Add(new ListItem(ds.Tables[0].Rows[i]["Name"].ToString(), ds.Tables[0].Rows[i]["ID"].ToString()));
                }
                cbl.DataBind();
            }
        }
    }

2.javascript访问DropDownList的值
<asp:DropDownList ID="txtADPID" runat="server" onchange="javascript:showADP(this)" >
 </asp:DropDownList>
 //判断是否显示广告位
      function showADP(obj)
        {
            var divname = document.getElementById("ADPostionName");
            //如果是网站广告就又广告位，其它都没有
            if(obj.options.value=="AdvS")//取得DropDownList的值
            {
               divname.style.display="block";
            }
            else
            {
               divname.style.display="none";
            }
        }
3.Javascript获取select的选中值和选中文本

var obj = document.getElementById(”select_id”); //selectid

var index = obj.selectedIndex; // 选中索引

var text = obj.options[index].text; // 选中文本

var value = obj.options[index].value; // 选中值