Killing a file?

[softwareguy74]

I want to delete a file each time I run a certain function just
to make sure the file does not already exist.

I used the following command at the start of the routine:

Kill "c:\es*.dat"

But, if the file doesn't already exist, I get an error..

How should I re-write the above code to only Kill if the files exists
or how to ignore the error (without using On Error Resume Next) if the file
doesn't exist?

Thanks for the help..

Dan

Try this:

If Dir("C:\file.exe") <> "" Then
Kill "C:\file.exe"
Else
Msgbox "Cannot delete file!", vbCritical
End If

[PaulLewis]

Because you want to delete the file if it exists and do not care about what happens if it does not exist. In this case, you are fine to simply ignore the VB error!

On Error Resume Next
Kill "C:\file.exe"
On Error GoTo 0
' the above line ensures that future errors are reported!

If you were in fact interested in the error,

On Error Resume Next
Kill "C:\file.exe"
If Err.Number <> 0 then
  MsgBox "uh oh"
Endif
On Error GoTo 0
' the above line ensures that future errors are reported!

Regards

But, if the file doesn't already exist, I get an error..

How should I re-write the above code to only Kill if the files exists
or how to ignore the error (without using On Error Resume Next) if the file
doesn't exist?

He said he didn't want to use On Error Resume Next .

[PaulLewis]

Matthew,
I know, but truly, it is the best way

I thought maybe he was avoiding using On Error... because maybe (sorry if I am wrong dbassettt74) he didn't know how to cancel the error trapping...

But to be fair - if there were other reasons why he did not want to use On Error... then I think your answer is pretty much as simple as it gets..

Cheers

[PaulLewis]

Why did I say that On Error Resume Next was best?

I couldn't remember why I always do it that way until just now:

If the file cannot be deleted for some reason (e.g. open file/read only etc) then you'll get an error which will need to be handled. So you HAVE to use On Error... because you don't know what could be happening on the machine that might cause you to fail to delete a file...

I hope that gets me off the hook

Cheers

Actually, that is a good idea. Incase the file exists and it's running. You cannot delete a running file. So that's where the On Error Resume Next comes in. Good thinking Paul.

By the way, here is also a way to delete an application if it is running. (Even though I said you can't...you can't do it with a normal the Kill function all by itself.) But here is how to end the running application if it's running (if it's not running, it won't do anything, but continue on to deleting the file) and then delete it:

Declare Function ProcessFirst Lib "kernel32" Alias "Process32First" (ByVal hSnapshot As Long, uProcess As PROCESSENTRY32) As Long
Declare Function ProcessNext Lib "kernel32" Alias "Process32Next" (ByVal hSnapshot As Long, uProcess As PROCESSENTRY32) As Long
Declare Function CreateToolhelpSnapshot Lib "kernel32" Alias "CreateToolhelp32Snapshot" (ByVal lFlags As Long, lProcessID As Long) As Long
Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long

Type PROCESSENTRY32
    dwSize As Long
    cntUsage As Long
    th32ProcessID As Long
    th32DefaultHeapID As Long
    th32ModuleID As Long
    cntThreads As Long
    th32ParentProcessID As Long
    pcPriClassBase As Long
    dwFlags As Long
    szexeFile As String * MAX_PATH
    End Type


Public Function KillApp(myName As String) As Boolean
    Const PROCESS_ALL_ACCESS = 0
    Dim uProcess As PROCESSENTRY32
    Dim rProcessFound As Long
    Dim hSnapshot As Long
    Dim szExename As String
    Dim exitCode As Long
    Dim myProcess As Long
    Dim AppKill As Boolean
    Dim appCount As Integer
    Dim i As Integer
    On Local Error GoTo Finish
    appCount = 0
    
    Const TH32CS_SNAPPROCESS As Long = 2&
    
    uProcess.dwSize = Len(uProcess)
    hSnapshot = CreateToolhelpSnapshot(TH32CS_SNAPPROCESS, 0&)
    rProcessFound = ProcessFirst(hSnapshot, uProcess)
    
    Do While rProcessFound
        i = InStr(1, uProcess.szexeFile, Chr(0))
        szExename = LCase$(Left$(uProcess.szexeFile, i - 1))
        If Right$(szExename, Len(myName)) = LCase$(myName) Then
            KillApp = True
            appCount = appCount + 1
            myProcess = OpenProcess(PROCESS_ALL_ACCESS, False, uProcess.th32ProcessID)
            AppKill = TerminateProcess(myProcess, exitCode)
            Call CloseHandle(myProcess)
        End If
        rProcessFound = ProcessNext(hSnapshot, uProcess)
    Loop

    Call CloseHandle(hSnapshot)
Finish:
End Function

Private Sub Command1_Click()
If Dir("C:\file.exe") <> "" Then
Call KillApp("C:\file.exe")
Kill ("C:\file.exe")
Else
Msgbox "Cannot delete file!", vbCritical
End If
End Sub