在两个下拉列表中同时访问数据的问题

我有两个下拉列表中的Web窗体..他们两个我用下面的代码来绑定与sql..but每当我试图结合第二个下拉与同method..it的给错误列表.. 我使用的代码：在两个下拉列表中同时访问数据的问题

protected void Page_Load(object sender, EventArgs e) 
    { 

     if (!IsPostBack) 
     { 

      ddlPropertyType.AppendDataBoundItems = true; 

      String strConnString = ConfigurationManager.ConnectionStrings["conString"].ConnectionString; 

      String strQuery = "select ID, PropertyName from PropertyType"; 

      SqlConnection con = new SqlConnection(strConnString); 

      SqlCommand cmd = new SqlCommand(); 

      cmd.CommandType = CommandType.Text; 

      cmd.CommandText = strQuery; 

      cmd.Connection = con; 

      try 
      { 

       con.Open(); 

       ddlPropertyType.DataSource = cmd.ExecuteReader(); 

       ddlPropertyType.DataTextField = "PropertyName"; 

       ddlPropertyType.DataValueField = "ID"; 

       ddlPropertyType.DataBind(); 

      } 

      catch (Exception ex) 
      { 
       throw ex; 
      } 

      finally 
      { 

       con.Close(); 

       con.Dispose(); 

      } 

     } 


    }

来源

2011-03-17 Prasad