Question

有没有办法在VBA（基本上是VB6）中查看文件，以便我知道文件何时被修改？ - 与this类似，只是我不想知道文件何时未使用，就在其修改时。

我发现的答案建议使用“FileSystemWatcher”和Win32 API“FindFirstChangeNotification”。我无法弄清楚如何使用这些，任何想法？

Answer 1

好的，我在VBA（VB6）中整理了一个能够检测文件系统更改的解决方案。

Public objWMIService, colMonitoredEvents, objEventObject

'call this every 1 second to check for changes'
Sub WatchCheck()
On Error GoTo timeout
    If objWMIService Is Nothing Then InitWatch 'one time init'
    Do While True
        Set objEventObject = colMonitoredEvents.NextEvent(1) 
         '1 msec timeout if no events'
        MsgBox "got event"

        Select Case objEventObject.Path_.Class
            Case "__InstanceCreationEvent"
                MsgBox "A new file was just created: " & _
                    objEventObject.TargetInstance.PartComponent
            Case "__InstanceDeletionEvent"
                MsgBox "A file was just deleted: " & _
                    objEventObject.TargetInstance.PartComponent
            Case "__InstanceModificationEvent"
                MsgBox "A file was just modified: " & _
                    objEventObject.TargetInstance.PartComponent
        End Select
    Loop
Exit Sub
timeout:
    If Trim(Err.Source) = "SWbemEventSource" And Trim(Err.Description) = "Timed out" Then
        MsgBox "no events in the last 1 sec"
    Else
        MsgBox "ERROR watching"
    End If
End Sub

将此子项复制并粘贴到上面附近，如果需要初始化全局变量，则会自动调用它。

Sub InitWatch()
On Error GoTo initerr
    Dim watchSecs As Integer, watchPath As String
    watchSecs = 1 'look so many secs behind'
    watchPath = "c:\\\\scripts" 'look for changes in this dir'

    strComputer = "."
    Set objWMIService = GetObject("winmgmts:\\" & strComputer & "\root\cimv2")
    Set colMonitoredEvents = objWMIService.ExecNotificationQuery _
        ("SELECT * FROM __InstanceOperationEvent WITHIN " & watchSecs & " WHERE " _
            & "Targetinstance ISA 'CIM_DirectoryContainsFile' and " _
                & "TargetInstance.GroupComponent= " _
                    & "'Win32_Directory.Name=""c:\\\\scripts""'")

    MsgBox "init done"
Exit Sub
initerr:
    MsgBox "ERROR during init - " & Err.Source & " -- " & Err.Description
End Sub

Answer 2

您应该考虑使用WMI临时事件使用者按照建议行here来查看文件，但将其缩小到特定文件而不是文件夹

（这假设您不能只关注文件的修改日期属性..）

Answer 3

看看here。该页面有一个由Bryan Stafford撰写的“Watch Directory Demo”VB样本。

Answer 4

我把它带入vb6，运行，显示：ERROR观看。

如何知道文件在VBA宏中的修改时间？

4 个答案: