以下示例显示了连接到Northwind数据库的简单ADO.NET应用程序，并返回类别列表的样子。该示例将输出写入控制台或命令提示符。<br>
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下面的示例显示了连接到Northwind数据库并返回类别列表的简单ADO.NET应用程序。该示例将输出写入控制台或命令提示符。<br>
<br>
sqlclient <br>
[Visual Basic] <br>
进口系统<br>
进口系统.data <br>
进口系统.data.sqlclient <br>
进口Microsoft.VisualBasic <br>
<br>
公共类样本<br>
<br>
＆nbsp; nbsp; public subs sub main（）<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp; dim nwindconn as sqlConnection = new SqlConnection（＆quot'data source = localhost;
＆nbsp;＆nbsp;＆nbsp; nbsp;＆nbsp; nbsp; nbsp; nbsp; nbsp; nbsp;＆nbsp;＆nbsp; p; ＆nbsp;＆nbsp;＆nbsp; nbsp;＆nbsp; nbsp; nbsp; nbsp; nbsp; nbsp;＆nbsp;＆nbsp; p; ＆nbsp;＆nbsp;＆nbsp;＆nbsp;＆quord＆quord＆quot of use id = sa; password = pwd; jirite catalog = northwind＆quort;
<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp; dim catcmd as sqlCommand = nwindconn.createcommand（）<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp; catcmd.commandText =＆quot; select categoryId，类别名称'
<br>
＆nbsp;＆nbsp;＆nbsp; nbsp; nwindconn.open（）<br>
<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp; dim myreader as sqldatareader = catcmd.executereader（）<br>
<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp;做myReader.read（）<br>
＆nbsp; nbsp;＆nbsp;＆nbsp;＆nbsp; nbsp; console.Writeline（vbtab {0}＆quort; <br>
＆nbsp;＆nbsp;＆nbsp; nbsp; loop <br>
<br>
＆nbsp;＆nbsp;＆nbsp; myreader.close（）<br>
＆nbsp;＆nbsp; nbsp; nbsp; nwindconn.close（）<br>
＆nbsp;＆nbsp; end sub <br>
结束课程<br>
[C＃] <br>
使用系统; <br>
使用System.Data; <br>
使用system.data.sqlclient; <br>
<br>
类样本<br>
{<br>
＆nbsp;＆nbsp; public static void main（）<br>
＆nbsp;＆nbsp; {<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp; sqlConnection nwindConn = new SqlConnection（data source = localhost; user id = sa; user id = sa; password = pwd; plitial catalog = northwind; northwind; <br>; <br>
<br>
”
＆nbsp;＆nbsp;＆nbsp;＆nbsp; catcmd.commandText =＆quot; select categoryId，类别名称'
<br>
＆nbsp;＆nbsp;＆nbsp; nbsp; nwindconn.open（）; <br>
<br>
”
<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp; while（myreader.read（））<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp; {<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp;＆nbsp;＆nbsp; console.writeline（＆quot; t {0}/t {1}＆quort; myreader.getInt32（0），myReader.getString（1））; <br>
＆nbsp;＆nbsp;＆nbsp;} <br>
<br>
＆nbsp;＆nbsp;＆nbsp; myreader.close（）; <br>
＆nbsp;＆nbsp; nbsp; nbsp; nwindconn.close（）; <br>
＆nbsp;＆nbsp;} <br>
} <br>
OLEDB <br>
[Visual Basic] <br>
进口系统<br>
进口系统.data <br>
进口系统.data.oledb <br>
进口Microsoft.VisualBasic <br>
<br>
公共类样本<br>
<br>
＆nbsp; nbsp; public subs sub main（）<br>
＆nbsp;＆nbsp; nbsp; nbsp; nbsp; dim nwindconn as oledbConnection = new oledbConnection（＆quot'provider = sqleledb; data source = localhost;
＆nbsp;＆nbsp;＆nbsp; nbsp;＆nbsp; nbsp; nbsp; nbsp; nbsp; nbsp;＆nbsp;＆nbsp; p; ＆nbsp;＆nbsp;＆nbsp; nbsp;＆nbsp; nbsp; nbsp; nbsp; nbsp; nbsp;＆nbsp;＆nbsp; p; ＆nbsp; nbsp; nbsp;＆nbsp; nbsp; nbsp; nbsp; nbsp;＆nbsp;＆nbsp;＆quert＆quort＆quot＆quot＆quot＆quot = sa; password = pwd; procastion = pwd; jirTial catalog = northwind＆quot = northwind;）<br>
<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp; dim catcmd as oledbCommand = nwindconn.createcommand（）<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp; catcmd.commandText =＆quot; select categoryId，类别名称'
<br>
＆nbsp;＆nbsp;＆nbsp; nbsp; nwindconn.open（）<br>
<br>
＆nbsp;＆nbsp;＆nbsp; nbsp; dim myreader as oledbdatareader = catcmd.executereader（）<br>
<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp;做myReader.read（）<br>
＆nbsp; nbsp;＆nbsp;＆nbsp;＆nbsp; nbsp; console.Writeline（vbtab {0}＆quort; <br>
＆nbsp;＆nbsp;＆nbsp; nbsp; loop <br>
<br>
＆nbsp;＆nbsp;＆nbsp; myreader.close（）<br>
＆nbsp;＆nbsp; nbsp; nbsp; nwindconn.close（）<br>
＆nbsp;＆nbsp; end sub <br>
结束课程<br>
[C＃] <br>
使用系统; <br>
使用System.Data; <br>
使用system.data.oledb; <br>
<br>
类样本<br>
{<br>
＆nbsp;＆nbsp; public static void main（）<br>
＆nbsp;＆nbsp; {<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp; oledbConnection nwindConn = new OledBConnection（＆quot'provider = sqleledB; data source; data source = localhost = localhost; user id = sa; password = sa; password = pwd; password = pwd; plitial catalog = northwind = northwind; <br>; <br>; <br>; <br>; <br>; <br>; <br>
<br>
”
＆nbsp;＆nbsp;＆nbsp;＆nbsp; catcmd.commandText =＆quot; select categoryId，类别名称'
<br>
＆nbsp;＆nbsp;＆nbsp; nbsp; nwindconn.open（）; <br>
<br>
＆nbsp;＆nbsp;＆nbsp; oledbdatareader myreader = catcmd.executereader（）; <br>
<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp; while（myreader.read（））<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp; {<br>
＆nbsp;＆nbsp;＆nbsp;＆nbsp;＆nbsp;＆nbsp; console.writeline（＆quot; t {0}/t {1}＆quort; myreader.getInt32（0），myReader.getString（1））; <br>
＆nbsp;＆nbsp;＆nbsp;} <br>
<br>
＆nbsp;＆nbsp;＆nbsp; myreader.close（）; <br>
＆nbsp;＆nbsp; nbsp; nbsp; nwindconn.close（）; <br>
＆nbsp;＆nbsp;} <br>
} <br>