asp.net(c#)同时执行多个select语句

        Hashtable hs = new Hashtable();
        int j = 0;
        SqlConnection con = Infcon.create();
        con.Open();
        SqlCommand cmd = new SqlCommand();
        cmd.Connection = con;
        cmd.CommandText = "select count(*)  from V_BYD_jc where average between 85 and 100;";
        cmd.CommandText += " select count(*)  from V_BYD_jc where average between 80 and 84;";
        cmd.CommandText += " select count(*)  from V_BYD_jc where average between 70 and 79";
        cmd.CommandText += " select count(*) from V_BYD_jc where average<=69 and average>0";
        cmd.CommandText += " select count(*) from V_BYD_jc where average=0;";
        cmd.CommandText += "select count(*) from v_byd_jc where jcsize='大';";
        cmd.CommandText += "select count(*) from v_byd_jc where jcsize='小'";
        SqlDataReader dr = cmd.ExecuteReader();
        do
        {
            if (dr.Read())
            {
                hs[j] = dr.GetInt32(0);//获取查询的结果
            }
            else
            {
                hs[j] = 0;//如果没有，则赋值为0
            }
            j++;
        } while (dr.NextResult());//读取下一个结果集