还是drowdownlist有关问题

还是drowdownlist问题
我在repeater加了一个drowdownlist！希望通过这个控件控制repeater中显示的数据！我的代码是protected void ddl_textchanged(object sender, EventArgs e)
  {
  foreach (RepeaterItem item in Repeater1.Items)
  { 
  DropDownList ddl = (DropDownList)item.FindControl("DrowDownList1");
  if (ddl.SelectedValue == "全部主题")
  {
  GetData();
  }
  else
  {
  model m = new model();
  m.MsgType = ddl.SelectedValue;
  m.U_Id = Session["UserId"].ToString();
  Repeater1.DataSource = Bll.GetAllMsgFromTypeAndUserId(m);
  Repeater1.DataBind();
  }
  }
  }

请问，这代码有错吗？请高手们指点

------解决方案--------------------------------------------------------
ddl是放repeater内部还是外部了
想控制repeater的数据 应该是放外面

C# code

protected void ddl_textchanged(object sender, EventArgs e)  {   if (DrowDownList1.SelectedValue == "全部主题")  {  GetData();  }  else  {  model m = new model();  m.MsgType = DrowDownList1.SelectedValue;  m.U_Id = Session["UserId"].ToString();  Repeater1.DataSource = Bll.GetAllMsgFromTypeAndUserId(m);  Repeater1.DataBind();  }    }