C# 更新gridview时出错？

更新gridview上的值时，我收到以下错误消息：

“对象引用未设置为对象的实例”

我的c代码是：

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您需要更新代码，以检查从gridview分配的控件是否为空。还要做一些异常处理

protected void gvDetails_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
  try
  {
  int nmbr = Convert.ToInt32(GridView1.DataKeys[e.RowIndex].Value.ToString());
  TextBox name = (TextBox)GridView1.Rows[e.RowIndex].FindControl("names");
  TextBox dept = (TextBox)GridView1.Rows[e.RowIndex].FindControl("depts");
  TextBox quantity = (TextBox)GridView1.Rows[e.RowIndex].FindControl("quantitys");
  //do check that any of your controls here is not null
  if(name!=null && dept!=null && quantity !=null)
  {
      con.Open();
      SqlCommand cmds=new SqlCommand("update erbp set name ='" + name.Text + "',dept ='"+ 
          dept.Text+"',quantity='" + quantity.Text + "' where inmbr=" + nmbr , con);
      cmds.ExecuteNonQuery();
      con.Close();
      GridView1.EditIndex = -1;
      BindEmployeeDetails();
  }
  }
  catch(Exception ex)       
  {
      //do exception handling here. 
  }
}

---

哪一行给您带来了错误？一个好的做法是始终测试FindControl是否实际返回了某些内容。您能告诉行号错误的来源吗？添加：A）使用参数化SQL；b） 使用SQL操作的

语句来清理资源。@Nithesh con不能是罪魁祸首，因为它在前一行中是打开的。如果该值为空，则会在前一行中给出错误。
protected void gvDetails_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
  try
  {
  int nmbr = Convert.ToInt32(GridView1.DataKeys[e.RowIndex].Value.ToString());
  TextBox name = (TextBox)GridView1.Rows[e.RowIndex].FindControl("names");
  TextBox dept = (TextBox)GridView1.Rows[e.RowIndex].FindControl("depts");
  TextBox quantity = (TextBox)GridView1.Rows[e.RowIndex].FindControl("quantitys");
  //do check that any of your controls here is not null
  if(name!=null && dept!=null && quantity !=null)
  {
      con.Open();
      SqlCommand cmds=new SqlCommand("update erbp set name ='" + name.Text + "',dept ='"+ 
          dept.Text+"',quantity='" + quantity.Text + "' where inmbr=" + nmbr , con);
      cmds.ExecuteNonQuery();
      con.Close();
      GridView1.EditIndex = -1;
      BindEmployeeDetails();
  }
  }
  catch(Exception ex)       
  {
      //do exception handling here. 
  }
}