新手求教Gridview后台绑定数据问题！在线等。。
我想问一下我用Gridview绑定了数据，可是为什么在显示器现实不出来的？

我页面的CS代码如下：
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;


public partial class edituser : System.Web.UI.Page
{

  protected void Page_Load(object sender, EventArgs e)
  {
   
  if (!Page.IsPostBack) bindgrid();
   
   
   
  }

  void bindgrid()
  {
  string sqlconnstr = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString; ;
  DataSet ds = new DataSet();

  using (SqlConnection sqlconn = new SqlConnection(sqlconnstr))
  {
  SqlDataAdapter sqld = new SqlDataAdapter("select UID,username,pwd,xm,tel,qq from users", sqlconn);
  sqld.Fill(ds, "users");



  }
  }

  protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e) 
  {

  GridView1.EditIndex = e.NewEditIndex;
  bindgrid();
   
  }

  protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
  {
  GridView1.EditIndex = -1;
  bindgrid();
   
  }

  protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
  {
  string sqlconnstr = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString; ;
  SqlConnection sqlconn = new SqlConnection(sqlconnstr);
  sqlconn.Open();
  String sql = "delete from users where UID= '" + GridView1.DataKeys[e.RowIndex].Value.ToString() + "'";
  SqlCommand Comm = new SqlCommand(sql, sqlconn);
  Comm.ExecuteNonQuery();
  sqlconn.Close();
  sqlconn = null;
  Comm = null;
  GridView1.EditIndex = -1;
  bindgrid();
   

  }
  protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
  {
  string sqlconnstr = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString; ;
  SqlConnection sqlconn = new SqlConnection(sqlconnstr);
  sqlconn.Open();
  SqlCommand Comm = new SqlCommand();
  Comm.Connection = sqlconn;
  Comm.CommandText = "update users set username=@username,pwd=@pwd,xm=@xm,tel=@tel,qq=@qq where UID=@UID";
  Comm.Parameters.AddWithValue("@UID",GridView1.DataKeys[e.RowIndex].Value.ToString());
  Comm.Parameters.AddWithValue("@username", ((TextBox)GridView1.Rows[e.RowIndex].Cells[1].Controls[0]).Text);
  Comm.Parameters.AddWithValue("@pwd", ((TextBox)GridView1.Rows[e.RowIndex].Cells[2].Controls[0]).Text);
  Comm.Parameters.AddWithValue("@xm", ((TextBox)GridView1.Rows[e.RowIndex].Cells[3].Controls[0]).Text);
  Comm.Parameters.AddWithValue("@tel", ((TextBox)GridView1.Rows[e.RowIndex].Cells[4].Controls[0]).Text);
  Comm.Parameters.AddWithValue("@qq", ((TextBox)GridVie