в 16:40, 26 мая 2010

2010-05-26T16:40:06Z

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2010-05-26T12:44:50Z

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==Available ADO.NET Data Providers==

<source lang="vbnet">

Imports System
Imports System.Data
Imports System.Data.rumon
Public Class MainClass
Public Shared Sub Main()
Using providers As DataTable = DbProviderFactories.GetFactoryClasses
For Each prov As DataRow In providers.Rows
Console.WriteLine(" Name:{0}", prov("Name"))
Console.WriteLine(" Description:{0}", prov("Description"))
Console.WriteLine(" Invariant Name:{0}", prov("InvariantName"))
Next
End Using
End Sub
End Class

</source>

==Generic Data Access==

<source lang="vbnet">
Imports System.Data.rumon
Imports System.Configuration
Module GenericDatabaseTest
Public Sub Main()
Dim Factory, Connection, Query As String
Factory = "Factory"
Connection = "Connection"
Query = "Query"
Dim Provider As DbProviderFactory
Provider = DbProviderFactories.GetFactory(Factory)
Dim con As DbConnection = Provider.CreateConnection()
con.ConnectionString = Connection
Dim Adapter As DbDataAdapter = Provider.CreateDataAdapter
Adapter.SelectCommand = Provider.CreateCommand()
Adapter.SelectCommand.Connection = con
Adapter.SelectCommand.rumandText = Query
Dim ds As New DataSet
Adapter.Fill(ds, "Orders")
For Each Row As DataRow In ds.Tables("Orders").Rows
Console.WriteLine(Row("OrderID"))
Next
End Sub
End Module

</source>

==Obtain the DbProviderFactory for SQL Server.==

<source lang="vbnet">

Imports System
Imports System.Data
Imports System.Data.rumon
Public Class MainClass
Public Shared Sub Main()
Dim factory As DbProviderFactory = DbProviderFactories.GetFactory("System.Data.SqlClient")
Using con As IDbConnection = factory.CreateConnection
con.ConnectionString = "Data Source=.\sqlexpress;Database=AdventureWorks;Integrated Security=SSPI;"
Using com As IDbCommand = con.CreateCommand
com.rumandType = CommandType.Text
com.rumandText = "SET ROWCOUNT 10;SELECT prod.Name, inv.Quantity FROM Production.Product prod INNER JOIN Production.ProductInventory inv ON prod.ProductID = inv.ProductID ORDER BY inv.Quantity DESC;"
con.Open()
Using reader As IDataReader = com.ExecuteReader
While reader.Read
Console.WriteLine(" {0} = {1}", reader("Name"), reader("Quantity"))
End While
End Using
con.Close()
End Using
End Using
End Sub
End Class

</source>

==OleDb Data Provider==

<source lang="vbnet">
Imports System
Imports System.Data
Imports System.Data.OleDb
Module OleDbProvider
Sub Main()
Dim ConnString As String = "provider=sqloledb;" & _
"data source=(local)\SQLEXPRESS;" & _
"integrated security=sspi;" & _
"database=MyDatabase"
Dim CmdString As String = "SELECT * FROM Employee"
Dim Conn As OleDbConnection
Dim Reader As OleDbDataReader
Try
Conn = New OleDbConnection(ConnString)
Conn.Open()
Dim Cmd As New OleDbCommand(CmdString, Conn)
Reader = Cmd.ExecuteReader()
Console.WriteLine("Querying database {0} with query {1}" & _
ControlChars.NewLine, Conn.Database, Cmd.rumandText)
Console.WriteLine("FirstName" & ControlChars.Tab & "LastName")
While (Reader.Read())
Console.WriteLine(Reader("FirstName").PadLeft(9) & _
ControlChars.Tab & Reader(1))
End While
Catch ex As Exception
Console.WriteLine("Error: {0}", ex)
Finally
Reader.Close()
Conn.Close()
End Try
End Sub
End Module

</source>

==SQL Server Data Provider==

<source lang="vbnet">
Imports System
Imports System.Data
Imports System.Data.OleDb
Module OleDbProvider
Sub Main()
" Set up connection string
Dim ConnString As String = "provider=sqloledb;" & _
"data source=(local)\SQLEXPRESS;" & _
"integrated security=sspi;" & _
"database=MyDatabase"
" Set up query string
Dim CmdString As String = "SELECT * FROM Employee"
"Declare Connection and DataReader variables
Dim Conn As OleDbConnection
Dim Reader As OleDbDataReader
Try
"Open Connection
Conn = New OleDbConnection(ConnString)
Conn.Open()
"Execute Query
Dim Cmd As New OleDbCommand(CmdString, Conn)
Reader = Cmd.ExecuteReader()
"Display output header
Console.WriteLine("Demonstrates the use " & _
"of the OleDb Data Provider." & ControlChars.NewLine)
Console.WriteLine("Querying database {0} with query {1}" & _
ControlChars.NewLine, Conn.Database, Cmd.rumandText)
Console.WriteLine("FirstName" & ControlChars.Tab & "LastName")
"Process The Result Set
While (Reader.Read())
Console.WriteLine(Reader("FirstName").PadLeft(9) & _
ControlChars.Tab & Reader(1))
End While
Catch ex As Exception
Console.WriteLine("Error: {0}", ex)
Finally
"Close Connection
Reader.Close()
Conn.Close()
End Try
End Sub
End Module

</source>

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в 16:40, 26 мая 2010

Admin: 1 версия