#region 登录验证
    /// <summary>
    /// asp.net登录验证的类
    /// </summary>
    /// <param name="sqls">sql语句</param>
    /// <param name="param">权限</param>
    /// <param name="users">用户名</param>
    /// <param name="pass">密码</param>
    /// <returns></returns>
    public bool login(string sqls, string param, string users, string pass)
    {
        string power = sql(sqls, param);
        sqls = sqls.ToLower();
        con.Open();
        com.CommandText = sqls;
        com.Connection = con;
        dr = com.ExecuteReader();
        if (dr.Read())
        {
            System.Web.HttpContext.Current.Session["id"] = users;
            System.Web.HttpContext.Current.Session["power"] = power;
            System.Web.HttpContext.Current.Session.Timeout = 10;
            return true;
        }
        else
        {
            return false;
        }
    }
    #endregion