Should Dispose() or Finalize() be used to delete temporary files?

Question

I have a class that makes use of temporary files (Path.GetTempFileName()) while it is active. I want to make sure these files do not remain on the user\'s hard driv

Answer 1

If you wish to re-use your temporary files e.g. open\close\read\write\etc, then clearing them up at the AppDomain unload level can be useful.

This can be used in combination with putting temp files in a well known sub-directory of a temp location and making sure that the directory is deleted on application startup to ensure unclean shut-downs are taken care of.

A basic example of the technique (with exception handling removed around delete for brevity). I use this technique in file-based unit tests where it makes sense and is useful.

public static class TempFileManager
{
    private static readonly List TempFiles = new List();
    private static readonly object SyncObj = new object();

    static TempFileManager()
    {
        AppDomain.CurrentDomain.DomainUnload += CurrentDomainDomainUnload;
    }

    private static void CurrentDomainDomainUnload(object sender, EventArgs e)
    {
        TempFiles.FindAll(file => File.Exists(file.FullName)).ForEach(file => file.Delete());
    }

    public static FileInfo CreateTempFile(bool autoDelete)
    {
        FileInfo tempFile = new FileInfo(Path.GetTempFileName());

        if (autoDelete)
        {
            lock (SyncObj)
            {
                TempFiles.Add(tempFile);
            }
        }

        return tempFile;
    }
}