我是否应该关心StreamWriter.Dispose（）是否抛出System.IO.IOException？

Question

I'm using a StreamWriter to write to a file over the network (Samba).

Sometimes, the network conditions are not so good and causes my write to fail. In that case, I want to just clean up and try starting a new file.

The problem is that, even when I try to clean up (ie calling Dispose() on my StreamWriter object), I get an IOException as it fails to flush (because the network conditions are bad, remember), like so:

System.IO.IOException
An unexpected network error occurred.

   at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
   at System.IO.FileStream.FlushWrite(Boolean calledFromFinalizer)
   at System.IO.FileStream.Flush(Boolean flushToDisk)
   at System.IO.StreamWriter.Dispose(Boolean disposing)
   at System.IO.TextWriter.Dispose()

Shall I care in such case? If I catch the IOException, shall I then try to somehow finish the clean up in other ways? Or do I just ignore the IOException and move along?

In other words, what should I do here?

try
{
    using (StreamWriter writer = new StreamWriter(some_network_file_path, /* ... */))
    {
        while (true)
        {
            /* append lines of csv-style data to the file. */
        }
    }
}
/* writer.Dispose() can throw an IOException as it fails to flush. */
catch (System.IO.IOException)
{
    /*
    What shall I do here, if anything at all?
    Suppose that my only concern is resource leak via the StreamWriter
    object.
    It's easy for me to clean up the data file later by discarding the last
    incomplete line.
    */
}

Answer 1

You should care about an error if you, well, care about:

• whether it happens or not, and
• the fact of it happening when it does.

The first thing to make clear for yourself here is the cause(s) of the error and the resulting impact of it happening or not happening on your application.

Eg if your I/O failed, you sigh and think your data is lost. But, on connection close (if your deduction is correct), a flush is attempted again, and if there's no error this time, your data actually isn't lost.