changing to a different StreamWriter constructor causing bad output

Question

I had this code

StreamWriter sw = new StreamWriter(this.FileName, true);
sw.WriteLine(text);
sw.Close();

Which I changed to this (because of a contention issue):

StreamWriter sw = new StreamWriter(
          new FileStream(this.FileName, FileMode.OpenOrCreate
               , FileAccess.ReadWrite, FileShare.Write)
          , Encoding.ASCII); 
sw.WriteLine(strLog);
sw.Close();

The issue is that the first one worked fine, outputted proper text that was human readable (this is for a log text file). The second one outputs totally screwy output, regardless of the Encoding type I've used. I've tried ASCII, UTF7, 8, Unicode and Default. So clearly I'm missing something fundamental about FileStream or TextWriter. Please edumacate me.

Answer 1

I've tried your code without being able to reproduce any weird behavior.

A few thoughts:

• You do not flush your StreamWriter or your FileStream.
• You do not call Dispose on your StreamWriter and FileStream. Try wrapping these in using statements.
• Ascii encoding is evil. I assume this is just a test step.
• FileMode.OpenOrCreate will ... open or create the file. It will open an already existing file and overwrite the first bytes. Do you want to use FileMode.Create to create a new file, or overwrite an existing?

EDIT:

The solution to the problem was to use FileMode.Append, per comments to this post.

Answer 2

Just to check the obvious, you have:

sw.WriteLine(text);

in the first example and

sw.WriteLine(strLog);

in the second. Without seeing all your code, I can't know the answer to the following so I feel compelled to ask:

Are test and strLog different things in your source, or is the difference only a typo?