asp.net中把数据库中数据读出来显示到页面

数据库连接：using System

using System.Collections

using System.Collections.Specialized

using System.Data

using System.Data.SqlClient

using System.Configurationnamespace DAL

{//数据库连接字符串

protected static string connectionString="server=.database=datauid=sapwd=sa"public static string ConnectionString

{

set { connectionString = value}

get { return connectionString}}/// <summary>执行查询语句，返回DataSet

/// </summary>

/// <param name="SQLString">查询语句</param>

/// <returns>DataSet</returns>

public static DataSet Query(string SQLString)

{

using (SqlConnection connection = new SqlConnection(connectionString))

{

DataSet ds = new DataSet()

try

{

connection.Open()

SqlDataAdapter command = new SqlDataAdapter(SQLString, connection)

command.Fill(ds, "ds")

}

catch (System.Data.SqlClient.SqlException ex)

{

throw new Exception(ex.Message)

}

return ds

}

} 查询类：using System

using System.Data

using System.Text

using System.Data.SqlClient

using System.Collections

using System.Collections.Generic

using Business.Modelsnamespace Business.SQLServerDAL

{/// <summary>

/// 数据访问类handbook。

/// </summary>

public partial class handbookService

{public handbookService()

{}/// <summary>

/// 获数据列表

/// </summary>

public DataSetGetList()

{

return DbHelperSQL.Query("select * from [2002handbook]")

}}} 页面后台.cshandbookService bll=new handbookService ()GridView1.DataSource=bll.GetList()GridView1.DataBind()

假设你下拉框已经绑定数据源，同时datatextfield和datavaluefield也绑定，那么：

using

(sqlconnection

con

=

new

sqlconnection("你的数据库字符连接串"))

{

sqlcommand

cmd

=

new

sqlcommand("select

top

1

字段名

from

表

where

字段名=@字段名")

cmd.parameters.addwithvalue("@字段名",dropdownlist1.selectedvalue)

con.open()

textbox1.text

=

cmd.executescalar().tostring()

}

注意：下拉列表autopostback=true

---