如何从数据库中查询出多个结果集或一个结果集

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Data.SqlClient;

namespace _11_26

{

public partial class lianxi2 : System.Web.UI.Page

{

protected void Page_Load(object sender, EventArgs e)

{

string constr = "data source=.\\SQLEXPRESSPC;initial catalog=School;user id=sa;password=admin";

using (SqlConnection con = new SqlConnection(constr))

{

string sql = "select * from Student;select * from Class";

using (SqlCommand cmd = new SqlCommand(sql, con))

{

con.Open();

using (SqlDataReader reader = cmd.ExecuteReader())

{

if (reader.HasRows)

{

#region 读取多个结果集的方法

//do-----while,do中先来读取第一个结果集，while（reader.NextResult()）中判断是否还有结果集，如果有在do中再次读取第二个结果集，一次类推------

do

{

if (reader.HasRows)

{

while (reader.Read())

{

//内层循环获取列

for (int i = 0; i < reader.FieldCount; i++)

{

Response.Write(reader.GetValue(i));

}

Response.Write("<br>");

}

}

}

while (reader.NextResult());

#endregion

#region 读取一个结果集的方法

//while (reader.Read())

//{

// //内层循环获取列

// for (int i = 0; i < reader.FieldCount; i++)

// {

// Response.Write(reader.GetValue(i));

// }

// Response.Write("<br>");

//}

#endregion

}

}

}

}

}

}

}