gridview RowDataBound事件绑定事只绑定第一行数据或者隔一行绑定，什么情况？

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
    {
      

        if (e.Row.RowType == DataControlRowType.DataRow)
        {
           

            string userid = e.Row.Cells[1].Text.ToString();
            string sql = "select * from tb_user where id = " + userid;
            if (co.execSQL(sql))
            {
                SqlDataReader reader = co.getRow(sql);
                reader.Read();
                e.Row.Cells[1].Text = reader["name"].ToString();
            }
        }