Check if file is in use


I want to check in my vb program if a specific file is in use. Only when the file isn't in use anymore, my program may continue?

Can somebody help?

Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Mike TomlinsonMiddle School Assistant TeacherCommented:
What you can do is attempt to open the file with exclusive read write access.  If the attempt fails, it must be in use by another process:

Option Explicit

Private Sub Command1_Click()
    If isFileInUse(Text1.Text) Then
        Label1.Caption = "File In Use"
        Label1.Caption = "File Available"
    End If
End Sub

Private Function isFileInUse(ByVal filename As String) As Boolean
    On Error GoTo openError
    isFileInUse = False ' assume it isn't locked
    If Dir(filename) <> "" Then
        ' attempt to get exclusive access to the file
        ' if exclusive access fails, we jump to openError:
        ' and return true
        Open filename For Binary Lock Read Write As #1
        Close #1
        MsgBox filename, vbCritical, "File Not Found"
    End If
    Exit Function

isFileInUse = True
End Function

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.