How To Back Up the NT Event Log in Visual Basic (216089)


The information in this article applies to:

  • Microsoft Visual Basic Standard Edition, 32-bit, for Windows 4.0
  • Microsoft Visual Basic Professional Edition, 32-bit, for Windows 4.0
  • Microsoft Visual Basic Enterprise Edition, 32-bit, for Windows 4.0
  • Microsoft Visual Basic Learning Edition for Windows 5.0
  • Microsoft Visual Basic Learning Edition for Windows 6.0
  • Microsoft Visual Basic Professional Edition for Windows 5.0
  • Microsoft Visual Basic Professional Edition for Windows 6.0
  • Microsoft Visual Basic Enterprise Edition for Windows 5.0
  • Microsoft Visual Basic Enterprise Edition for Windows 6.0
This article was previously published under Q216089

SUMMARY

Event logging in Windows provides a standard, centralized way for Windows and applications to record important software and hardware events. It also supplies a standard user interface for viewing the logs and a programming interface for examining the logs.

This article illustrates how to back up the NT Event Log with Visual Basic versions 4.0 and later. This can be done using the BackupEventLog API call. While Visual Basic versions 5.0 and later have built-in functionality for event-logging, they do not provide the backup functionality that the Win32 API does.

MORE INFORMATION

The following example shows how to back up the local Application Event Log to a file named appback.evt:

Step by Step Example

  1. Create a new standard project in Visual Basic. Form1 is created by default.
  2. Add a CommandButton to Form1 and change its name to cmdBackupEventLog .
  3. Add the following code to the Form1 code window:
    Private Declare Function BackupEventLog Lib "advapi32.dll" Alias "BackupEventLogA" ( _
    ByVal hEventLog As Long, _
    ByVal lpBackupFileName As String) _
    As Long

Private Declare Function CloseEventLog Lib "advapi32.dll" ( _
    ByVal hEventLog As Long) _
    As Long

Private Declare Function OpenEventLog Lib "advapi32.dll" Alias "OpenEventLogA" ( _
    ByVal lpUNCServerName As String, _
    ByVal lpSourceName As String) _
    As Long

Private Sub cmdBackupEventLog_Click()
    Dim hEventLog As Long
    Dim lretv As Long
    
    hEventLog = OpenEventLog(VBNullString, "Application")
    If hEventLog = 0 Then
         Debug.Print "OpenEventLog Failed"
         Exit Sub
    End If
    
    lretv = BackupEventLog(hEventLog, "appback.evt")
    If lretv = 0 Then
         Debug.Print "BackupEventLog Failed"
         Exit Sub
    End If
                
    lretv = CloseEventLog(hEventLog)
    If lretv = 0 Then
         Debug.Print "CloseEventLog Failed"
         Exit Sub
    End If

End Sub
  4. Press the F5 key to run the project and click cmdBackupEventLog. This backs up the Event Log to the file appback.evt.

REFERENCES

For additional information about event logging from Visual Basic, click the article numbers below to view the articles in the Microsoft Knowledge Base:

154576 How To Write to the NT Event Log from Visual Basic

161306 INFO: App.LogEvent Only Logs in Compiled Applications

184747 INFO: Event Logging in Visual Basic

216097 How To Clear the NT Event Log in Visual Basic

216146 How To Get the Number of NT Event Log Records in Visual Basic

Modification Type:MinorLast Reviewed:6/29/2004
Keywords:kbAPI kbEventLog kbhowto KB216089
©2004 Microsoft Corporation. All rights reserved.