Is there a way I can check to see if the file is already open?

Question

I want to check if C:\Data.xlsb is already open or not.

I have got following code from here How to tell if a certain Excel file is open using VB.NET?

Public Shared Function OpenUnlockedFile(ByVal path As String) As StreamWriter
Dim sw As StreamWriter = nothing
Try
    sw = New StreamWriter(path)
Catch ex As IOException When System.Runtime.InteropServices.Marshal.GetLastWin32Error() = 32
    REM locked, return nothing
End Try
Return sw
End Function

But I dont know how to use the code above.

I prefer sub instead of function.

Best regards.

Answer 1

To use this code, you would use the function as in the following example:

Imports System.IO

Public Class Form1
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        If OpenUnlockedFile("C:\Data.xlsb") Is Nothing Then
            MessageBox.Show("File is locked")
        End If
    End Sub

    Public Shared Function OpenUnlockedFile(ByVal path As String) As StreamWriter
        Dim sw As StreamWriter = Nothing
        Try
            sw = New StreamWriter(path)
        Catch ex As IOException When System.Runtime.InteropServices.Marshal.GetLastWin32Error() = 32
        REM locked, return nothing
        End Try
        Return sw
    End Function

End Class

The function, OpenUnlockedFile("C:\Data.xlsb") is run whenever you press Button1 (in this example). If the function is run and it returns Nothing, then you will know the file is locked.

Please note that you will also need

Imports System.IO

for this example to work.