如何知道VBA宏中的文件何時被修改？

Question

有沒有辦法在VBA中觀察文件（實際上是VB6），以便知道文件何時被修改？ - 類似this只我不想知道什麼時候一個文件是未使用，就是當它的修改爲。

我發現的答案建議使用「FileSystemWatcher」和Win32 API「FindFirstChangeNotification」。我不知道如何使用這些，但任何想法？

Answer 1

好吧，我在VBA（VB6）中彙總了一個能夠檢測文件系統更改的解決方案。

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 

複製粘貼這個子接近上面，它會自動調用，如果需要初始化全局變量。

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

你應該考慮使用WMI臨時事件消費者看文件，沿線建議here但縮小它歸結爲一個特定的文件夾

，而不是（這是假設你不能只是保持一個注意文件的修改日期屬性..）

Answer 3

看一看here。該頁面由Bryan Stafford提供「Watch Directory Demo」VB示例。

Answer 4

我把它放到vb6中，運行，顯示：ERROR在看。