the following example shows what a simple ado.net application that connects to the northwind database and returns a list of categories would look like. the example writes the output to the console, or command prompt.

the following example shows what a simple ado.net application that connects to the northwind database and returns a list of categories. the example writes the output to the console, or command prompt.

sqlclient

[visual basic]

imports system

imports system.data

imports system.data.sqlclient

imports microsoft.visualbasic

public class sample

public shared sub main()

dim nwindconn as sqlconnection = new sqlconnection(data source=localhost; & _

user id=sa;password=pwd;initial catalog=northwind)

dim catcmd as sqlcommand = nwindconn.createcommand()

catcmd.commandtext = select categoryid, categoryname from categories

nwindconn.open()

dim myreader as sqldatareader = catcmd.executereader()

do while myreader.read()

console.writeline(vbtab & {0} & vbtab & {1}, myreader.getint32(0), myreader.getstring(1))

loop

myreader.close()

nwindconn.close()

end sub

end class

[c#]

using system;

using system.data;

using system.data.sqlclient;

class sample

{

public static void main()

{

sqlconnection nwindconn = new sqlconnection(data source=localhost;user id=sa;password=pwd;initial catalog=northwind);

sqlcommand catcmd = nwindconn.createcommand();

catcmd.commandtext = select categoryid, categoryname from categories;

nwindconn.open();

sqldatareader myreader = catcmd.executereader();

while (myreader.read())

{

console.writeline(t{0}t{1}, myreader.getint32(0), myreader.getstring(1));

}

myreader.close();

nwindconn.close();

}

}

oledb

[visual basic]

imports system

imports system.data

imports system.data.oledb

imports microsoft.visualbasic

public class sample

public shared sub main()

dim nwindconn as oledbconnection = new oledbconnection(provider=sqloledb;data source=localhost; & _

user id=sa;password=pwd;initial catalog=northwind)

dim catcmd as oledbcommand = nwindconn.createcommand()

catcmd.commandtext = select categoryid, categoryname from categories

nwindconn.open()

dim myreader as oledbdatareader = catcmd.executereader()

do while myreader.read()

console.writeline(vbtab & {0} & vbtab & {1}, myreader.getint32(0), myreader.getstring(1))

loop

myreader.close()

nwindconn.close()

end sub

end class

[c#]

using system;

using system.data;

using system.data.oledb;

class sample

{

public static void main()

{

oledbconnection nwindconn = new oledbconnection(provider=sqloledb;data source=localhost;user id=sa;password=pwd;initial catalog=northwind);

oledbcommand catcmd = nwindconn.createcommand();

catcmd.commandtext = select categoryid, categoryname from categories;

nwindconn.open();

oledbdatareader myreader = catcmd.executereader();

while (myreader.read())

{

console.writeline(t{0}t{1}, myreader.getint32(0), myreader.getstring(1));

}

myreader.close();

nwindconn.close();

}

}

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