Example: Check if a file is in use by another process

[jumper77]

I've noticed that people ask about this a lot on the net. I had my time struggling with it too and that's why I made this function.

   Public Function IsFileInUse(sFile As String) As Boolean
        Try
            Using f As New IO.FileStream(sFile, FileMode.Open, FileAccess.ReadWrite, FileShare.None)
            End Using
        Catch Ex As Exception
            Return True
        End Try
        Return False
    End Function

You should check to see if the file exists before calling this function.
I know there are other and most likely better ways of doing this, but this works for me.

[JuggaloBrotha]

I've noticed that people ask about this a lot on the net. I had my time struggling with it too and that's why I made this function.

   Public Function IsFileInUse(sFile As String) As Boolean
        Try
            Using f As New IO.FileStream(sFile, FileMode.Open, FileAccess.ReadWrite, FileShare.None)
            End Using
        Catch Ex As Exception
            Return True
        End Try
        Return False
    End Function

You should check to see if the file exists before calling this function.
I know there are other and most likely better ways of doing this, but this works for me.

Should add the file exists to this function so it's self contained. Also note that this well return False if a file is marked as ReadOnly, you can add a check for that before trying to see if a file is in use and return arbitrarily return a True or False for ReadOnly files since your app wont be able to write to it anyways.

[jumper77]

Hi, I apologize, I didn't see your reply until just now. Not sure how I missed it. You are correct about checking for file exists. And the check for "read-only" is a great idea and I did not think of that. Your post has made this function much better.