VB.net – How to properly close a text file after reading so it can be opend for writing in the same application

I have a text file that I want to read into a buffer then close it. Later on in the program I want to open the same file to append to it. I get the all too familiar error, that the file can’t be opened because it’s being used by another process, when I try to open it to write to it.

Here is the READ code:

If File.Exists(outfile) Then
    '  Load existing CSV file into csvFIle string to be used a check for duplicates
    rdr = New StreamReader(outfile)
    csvFile = rdr.ReadToEnd
    rdr.Close()
    rdr.Dispose()
    rdr = Nothing '
End If

And this is the code to open for WRITING:

        sw = New StreamWriter(outfile, True) ' append to file
        If newFL Then   ' if the file is new then write the HEADER to the file
            If outbuff > "" Then sw.WriteLine(outbuff)
            outbuff = ""
            newFL = False
        End If

There has got to be a way to completely release the file.
Any help would be greatly appreciated.

Thanks
Nor

>Solution :

Tried to re-create your issue and could not.

    Dim path As String = Environment.GetFolderPath(Environment.SpecialFolder.Desktop)
    path = IO.Path.Combine(path, "Test.txt")

    Dim line As String
    Using rdr As New IO.StreamReader(path)
        line = rdr.ReadLine
    End Using

    Using wrtr As New IO.StreamWriter(path, True)
        wrtr.WriteLine(line)
    End Using

Makes me suspect that the problem is in the code we aren’t seeing.