protected void Page_Load(object sender, EventArgs e)
{

// 初次加载网页页面时才绑定
if (!IsPostBack)
{
BusinessLogic bll = new BusinessLogic();

// 获得数据库查询“D00001”下拉框相匹配数据信息
DataTable dt = bll.GetData("D00001");

// 给下拉框绑定数据源

ddldata.DataSource = dt;

// 绑定下拉框的text值
ddldata.DataTextField = "AREA";

// 绑定下拉框的value值
ddldata.DataValueField = "AREA";

ddldata.DataBind();

// 在头部插进一条空的item
ddldata.Items.Insert(0, new ListItem("", ""));

}
}