[C#] [CF] [VS 2005 B2] FileStream ?

Here is a sample file.

line1 line2 line3 line4 line5 line6

here is the reading code...

FileStream fileStream = new FileStream(generatedPath, FileMode.OpenOrCreate);StreamWriter streamWriter = new StreamWriter(fileStream); StreamReader streamReader = new StreamReader(fileStream); CSLogger.Debug("stream length = " + fileStream.Length); CSLogger.Debug("read {0} pos {1} ", streamReader.ReadLine(), fileStream.Position); CSLogger.Debug("read {0} pos {1} ", streamReader.ReadLine(), fileStream.Position); CSLogger.Debug("read {0} pos {1} ", streamReader.ReadLine(), fileStream.Position); CSLogger.Debug("read {0} pos {1} ", streamReader.ReadLine(), fileStream.Position); CSLogger.Debug("read {0} pos {1} ", streamReader.ReadLine(), fileStream.Position);

and now the log file...

2005/07/21 - 16:42:43:000 #Debug Level# stream length = 45 2005/07/21 - 16:42:43:000 #Debug Level# read line1 pos 45 2005/07/21 - 16:42:43:000 #Debug Level# read line2 pos 45 2005/07/21 - 16:42:43:000 #Debug Level# read line3 pos 45 2005/07/21 - 16:42:43:000 #Debug Level# read line4 pos 45 2005/07/21 - 16:42:43:000 #Debug Level# read line5 pos 45

lmussier at 2007-9-9 >

FileStream.Position is the same as FileStream.Length in this case because StreamReader maintains an internal buffer on top of FileStream. When you do a StreamReader.ReadLine(), the internal buffer is filled with the actual contents of the FileStream object, in this case the contents of the entire file. This explains why the FileStream position stays the same as you read through the file with StreamReader. To obtain positional information about the file, either count the size of the array returned by StreamReader.ReadLine(), or use FileStream.Read() directly.

Cheers,
Anthony [MSFT]

AnthonyWong at 2007-9-9 >