VB.Net Tutorial/Database ADO.net/OleDbConnection — различия между версиями

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Текущая версия на 12:56, 26 мая 2010

Create OleDbConnection to Access database

Imports System.Data
Module Test
    Sub Main()
        Dim sConnectionString, sSQL As String
        
        "SQL Connection String
      sConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=c:\yourdatabase.mdb"
        sSQL = "SELECT Title FROM yourTable"
        Dim conn As New System.Data.OleDb.OleDbConnection(sConnectionString)
        Dim cmd As New System.Data.OleDb.OleDbCommand(sSQL, conn)
        Dim dr As System.Data.OleDb.OleDbDataReader
        conn.Open()
        dr = cmd.ExecuteReader()
        Do While dr.Read()
            System.Console.WriteLine(dr.Item("Title"))
        Loop
        dr.Close()
        conn.Close()
    End Sub
End Module

Create OleDbConnection to Sql server

Imports System.Data
Module Test
    Sub Main()
        Dim sConnectionString, sSQL As String
        
        "SQL Connection String
      sConnectionString = "Provider=SQLOLEDB.1;User ID=sa;Initial Catalog=YourDataBase;Data Source=(local)"
        sSQL = "SELECT Title FROM yourTable"
        Dim conn As New System.Data.OleDb.OleDbConnection(sConnectionString)
        Dim cmd As New System.Data.OleDb.OleDbCommand(sSQL, conn)
        Dim dr As System.Data.OleDb.OleDbDataReader
        conn.Open()
        dr = cmd.ExecuteReader()
        Do While dr.Read()
            System.Console.WriteLine(dr.Item("Title"))
        Loop
        dr.Close()
        conn.Close()
    End Sub
End Module

Using sql statement

Option Strict On
Imports System.Data
Imports System.Data.OleDb
Public Module UsingStatement
   Public Sub Main()
      Dim conn As New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=NorthWind.mdb")
      Dim cmd As New OleDbCommand
      Dim dr As OleDbDataReader
      Using conn
         conn.Open
         cmd.rumandText = "Select * From Customers"
         cmd.rumandType = CommandType.Text
         cmd.Connection = conn
         dr = cmd.ExecuteReader()
         If dr.HasRows Then
            Do While dr.Read()
               " Get first and last name of customer
               Console.WriteLine(CStr(dr.Item(1)) & " " & CStr(dr.Item(2)))
            Loop
         Else
            Console.WriteLine("The table has no rows.")
         End If
      End Using
   End Sub
End Module