string dbname = Server.MapPath("App_Data/basketball.mdb");

        OleDbConnection conn = new OleDbConnection("Provider=Microsoft.Jet.OleDb.4.0; Data Source=" + dbname);
        conn.Open();
        OleDbDataAdapter da = new OleDbDataAdapter("select qian from t_arranges where quautity<2", conn);//quautity字段表示被抽次数
        DataSet ds = new DataSet();
        da.Fill(ds, "t_table");
        DataRow[] rows = ds.Tables[0].Select();
        int counts = rows.Length;
        if (counts > 0)  
        else
        {
            Response.Write("<script language=javascript>alert('比赛时间还没有确定！');</script>");
        }
      
            Hashtable ht = new Hashtable();
            for (int i = 1; i < counts + 1; i++)
            {
                string qian = rows[i - 1]["qian"].ToString();  //qian字段表示设置的签值
               ht.Add(i.ToString(), qian);   
            }
        4.声明一个Random对象。
            Random rdm = new Random();
    5.让Random对象从哈希表的键中随机产生一个值
            counts = counts + 1;
            string random = rdm.Next(1, counts).ToString().Trim();
     6.用随机产生的键去访问哈希表的值。
      string qvalue = (string)ht[random];
     7.提交数据库……