GridView_RowUpdating取不到新值的解决方法

protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
    {
        sqlcon = new SqlConnection(strCon);
        sqlcon.Open();
        string bianhao = Convert.ToString(this.GridView1.DataKeys[e.RowIndex].Value);
        string beizhu = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[6].Controls[0])).Text.ToString();
        string sqlstr = "SQL語句'";
        sql = new SqlCommand(sqlstr, sqlcon);
        sql.ExecuteNonQuery();
        sqlcon.Close();
        GridView1.EditIndex = -1;
        bind();
    }

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