再谈 N 个 ASP.net DropDownList 无刷新联动菜单[2]

webform2.aspx

 private void Page_Load(object sender, System.EventArgs e)
  {
   // 在此处放置用户代码以初始化页面
   if(this.Request["state"]!=null)
   {　　
    string state = this.Request["state"].ToString();　　
    SqlConnection con = new SqlConnection("packet size=4096;user id=sa;data source=SERVER;persist security info=False;initial catalog=pubs");
    SqlDataAdapter da = new SqlDataAdapter("select address from authors where state = '"+state+"'",con);　　
    DataSet ds = new DataSet("address");　　
    da.Fill(ds);　　
    XmlTextWriter writer = new XmlTextWriter(Response.OutputStream, Response.ContentEncoding);　　
    writer.Formatting = Formatting.Indented;　　
    writer.Indentation = 4;　　
    writer.IndentChar = ' ';　　
    ds.WriteXml(writer);　　
    writer.Flush();　　
    Response.End();　　
    writer.Close();　　
   }
  }