我正在尝试创建一个脚本,它将查看本地计算机上的特定.txt文件,获取它的DateLastModified属性,并将其与上次检查时的上一个/上一个值进行比较(在一个循环中,每1-2秒一次) )。
循环(每秒运行一次)会增加一个计数器,如果计数器达到一个限制(比如说10秒),一段代码就会执行“杀死/终止”特定进程/ .exe的任务,这可能会挂起,然后重新启动它。
我发现一些非常好的.vbs在线样本使用订阅事件,我不认为这是我想要/需要去的路线,因为脚本实际上需要连续运行而不是仅在特定文件时异步被修改了。
编辑:我正在寻找一个提供“看门狗”功能的VBScript,通过监视.txt文件进行修改。脚本应该每秒运行一个循环来检查修改,如果没有修改,则增加一个计数器。一旦计数器达到限制(10秒?),它将终止一个固定进程(硬编码为VBScript中的参数),然后重新启动进程(作为VBScript中参数的进程路径)。
到目前为止,我还没有找到一个很好的例子。我一直在玩其他使用objWMIService.ExecNotificationQuery(Query)
的例子,这似乎很酷,因为使用了很少的开销(本质上是异步的) - 它似乎不符合我的需要,如上所述。
如果我必须分享我发现的并且一直在玩弄...好......这里是:
intInterval = "1"
strDrive = "C:"
strFolder = "\\Project\\"
strComputer = "."
intTmrVal = 0
Set objWMIService = GetObject( "winmgmts:" & "{impersonationLevel=impersonate}!\\" & strComputer & "\root\cimv2" )
strQuery = "Select * From __InstanceOperationEvent" _
& " Within " & intInterval _
& " Where Targetinstance Isa 'CIM_DataFile'" _
& " And TargetInstance.Name='C:\\Project\\test.txt'"
Set colEvents = objWMIService.ExecNotificationQuery(strQuery)
Do
Set objEvent = colEvents.NextEvent()
Set objTargetInst = objEvent.TargetInstance
Select Case objEvent.Path_.Class
Case "__InstanceCreationEvent"
WScript.Echo "Created: " & objTargetInst.Name
Case "__InstanceDeletionEvent"
WScript.Echo "Deleted: " & objTargetInst.Name
Case "__InstanceModificationEvent"
Set objPrevInst = objEvent.PreviousInstance
For Each objProperty In objTargetInst.Properties_
If objProperty.Value <> objPrevInst.Properties_(objProperty.Name) Then
WScript.Echo "Changed: " & objTargetInst.Name
WScript.Echo "Property: " & objProperty.Name
WScript.Echo "Previous value: " & objPrevInst.Properties_(objProperty.Name)
WScript.Echo "New value: " & objProperty.Value
End If
Next
End Select
'Count how many times it has been modified // just playing with a counter
If objEvent.TargetInstance.LastModified <> objEvent.PreviousInstance.LastModified Then
intTmrVal = intTmrVal+1
WScript.Echo "Changed: " & intTmrVal & " times"
WScript.Echo
End If
Loop
一种简单的方法是直接在WMI请求中为下一个事件设置超时
Option Explicit
Const MONITOR_FILE = "c:\temp\test.txt"
Const MONITOR_LIMIT = 10
Dim wmi
Set wmi = GetObject( "winmgmts:" & "{impersonationLevel=impersonate}!\\.\root\cimv2" )
Dim query
query = "SELECT * FROM __InstanceOperationEvent WITHIN 1 " _
& " WHERE TargetInstance ISA 'CIM_DataFile' " _
& " AND TargetInstance.Name='" & Replace(MONITOR_FILE, "\", "\\") & "'"
Dim colEvents
Set colEvents = wmi.ExecNotificationQuery( query )
Dim currentEvent
Do
' Flag value
Set currentEvent = Nothing
' Try to get the next event with a timeout limit
' If a timeout happens we need to catch raised error
On Error Resume Next
Set currentEvent = colEvents.NextEvent( MONITOR_LIMIT * 1000 )
On Error GoTo 0
' If there is not an event there was a timeout
If currentEvent Is Nothing Then
Exit Do
End If
Loop
WScript.Echo "File has not been changed for " & MONITOR_LIMIT & " seconds."
事件观察者在事件发生时对事件作出反应。但是,您希望对未发生的事件(即未修改的文件)做出反应。出于显而易见的原因,您无法使用事件监视器。
您需要的是检查文件上次修改日期的代码
path = "C:\Project\test.txt"
Set fso = CreateObject("Scripting.FileSystemObject")
ts = fso.GetFile(path).DateLastModified
然后,如果该时间戳大于x秒/分钟,则终止给定进程
pname = "foo.exe"
wmi = GetObject("winmgmts://./root/cimv2")
qry = "SELECT * FROM Win32_Process WHERE Name='" & pname & "'"
If DateDiff("s", ts, Now) > 10 Then
For Each p In wmi.ExecQuery(qry)
p.Terminate
Next
End If
但是,Windows任务计划程序不支持每秒(或每2秒)运行任务所需的粒度。即使它确实如此,每秒产生一个新进程对于系统性能起初并不是很好。您可以设置每日计划,然后指示任务计划程序在一天的持续时间内每5分钟重新运行一次任务。您需要在脚本中考虑的其余部分。
定义5分钟超时并在循环中重新运行检查,直到超时到期:
interval = 2 'seconds
timeout = 5 'minutes
endtime = DateAdd("n", timeout, Now)
sleeptime = interval * 1000 'milliseconds
Do
'check and process handling go here
WScript.Sleep sleeptime
Loop Until Now >= endtime
由于fso
和wmi
可以重复使用,因此不要通过在循环内反复重新定义它们来浪费资源。在脚本开头只定义一次。