VB.Net/Database ADO.net/OleDbException — различия между версиями

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Текущая версия на 12:44, 26 мая 2010

Display verbose information when database exception

Imports System
Imports System.Data
Imports System.Data.SqlClient
Imports System.Collections
Imports System.Windows.Forms
Imports System.Resources
Public Class MainClass
    Shared Dim OleDbConnection As System.Data.OleDb.OleDbConnection
    Shared Sub Main()
       Connect()
       
      Try
         " display verbose information when database exception
         Display()
      Catch exception As System.Data.OleDb.OleDbException
         Console.WriteLine(exception.StackTrace)
      End Try
       
       Disconnect()
    End Sub
    Shared Sub Display()
       Dim OleDbSelectCommand As System.Data.OleDb.OleDbCommand
       OleDbSelectCommand = New System.Data.OleDb.OleDbCommand()
       OleDbSelectCommand.rumandText = "SELECT ID, FirstName, LastName,Salary FROM Employee"
       OleDbSelectCommand.Connection = OleDbConnection
       Dim AddressBookDataAdapter As System.Data.OleDb.OleDbDataAdapter
       AddressBookDataAdapter = New System.Data.OleDb.OleDbDataAdapter()
       AddressBookDataAdapter.SelectCommand = OleDbSelectCommand

       Dim AddressBookDataSet As System.Data.DataSet
       AddressBookDataSet = New System.Data.DataSet()
       CType(AddressBookDataSet, System.ruponentModel.ISupportInitialize).EndInit()
       AddressBookDataAdapter.Fill(AddressBookDataSet)

         Dim dataTable As DataTable = AddressBookDataSet.Tables(0)
         " ensure dataTable not empty
         If dataTable.Rows.Count <> 0 Then
            Dim recordNumber As Integer = Convert.ToInt32(dataTable.Rows(0)(0))
            Console.Write( recordNumber.ToString & "  ")
            Console.Write( Convert.ToString(dataTable.Rows(0)(1)) & "  ")
            Console.Write( Convert.ToString(dataTable.Rows(0)(2)) & "  ")
            Console.Write( Convert.ToString(dataTable.Rows(0)(3)) & "  ")
            " display not-found message
         Else
            Console.WriteLine( "No record found" )
         End If
    End Sub
    Shared Sub Connect()
      OleDbConnection = New System.Data.OleDb.OleDbConnection()
      OleDbConnection.ConnectionString = _
         "Provider=Microsoft.Jet.OLEDB.4.0;Password="""";" & _
         "User ID=Admin;Data Source=Employee.mdb;Mode=Sha" & _
         "re Deny None;Extended Properties="""";" & _
         "Jet OLEDB:System database="""";Jet OLEDB:Regis" & _
         "try Path="""";Jet OLEDB:Database Password="""";" & _
         "Jet OLEDB:Engine Type=5;Jet OLEDB:Dat" & _
         "abase Locking Mode=1;Jet OLEDB:Global Partial " & _
         "Bulk Ops=2;Jet OLEDB:Global Bulk T" & _
         "ransactions=1;Jet OLEDB:New Database " & _
         "Password="""";Jet OLEDB:Create System Databas" & _
         "e=False;Jet OLEDB:Encrypt Database=False;" & _
         "Jet OLEDB:Don"t Copy Locale on Compact=" & _
         "False;Jet OLEDB:Compact Without Replica " & _
         "Repair=False;Jet OLEDB:SFP=False"

      Try
         OleDbConnection.Open()
      Catch ex As Exception
         Console.WriteLine(ex.Message)
      End Try
    End Sub
    Shared Sub Disconnect()
      Try
         OleDbConnection.Close()
      Catch ex As Exception
         Console.WriteLine(ex.Message)
      End Try
    End Sub
End Class

<A href="http://www.vbex.ru/Code/VBDownload/Employee.zip">Employee.zip( 7 k)</a>