asp.net 向UpdatePaneel中动态添加DropDownList控件代码

asp教程.net 向updatepaneel中动态添加dropdownlist控件代码

//aspx文件中添加如上代码，showchildlist函数如下：
  protected void showchildlist(object sender, eventargs e)
  {
  dropdownlist ddl_now = (dropdownlist)sender;
  string sql = "select part_id,part_name from tb_parts where root_id='" + ddl_now.selectedvalue.tostring() + "'";
  sqldatareader dr = means.getcom(sql);
  if (dr.hasrows)
  {
  dropdownlist ddl_new = new dropdownlist();
  ddl_new.selectedindexchanged += new system.eventhandler(this.childlist);
  ddl_new.autopostback = true;
  listitem li = new listitem();
  li.value = "-1";
  li.text = "请选择栏目...";
  li.selected = true;
  ddl_new.items.add(li);
  while (dr.read())
  {
  listitem li2 = new listitem();
  li2.value = dr["part_id"].tostring();
  li2.text = dr["part_name"].tostring();
  ddl_new.items.add(li2);
  }
  ddl_now.parent.controls.add(ddl_new);
  }
  }