CODEWITHSUNDEEP
c#filestream
loles
loles

Reputation: 139

FileStream, only producing one result?

I have two filestreams which collects different information from different files:

FileStream dataStruc = new FileStream("c:\\temp\\dataStruc.txt", FileMode.Create, FileAccess.ReadWrite);

FileStream csvFile = new FileStream("c:\\temp\\" + fileName + ".txt", FileMode.Create, FileAccess.ReadWrite);

StreamWriter sw = new StreamWriter(csvFile);
StreamWriter swc = new StreamWriter(dataStruc);

when both streamwriters are used to get the same piece of information like shown below: 

sw.WriteLine(sheet); 
swc.WriteLine(sheet);

then sw streamwriter has information from file. Have I set up my filestreams incorrectly?

Upvotes: 2

Views: 273

Answers (2)

Jens H
Jens H

Reputation: 4632

I suppose that you have conflicting concurrent access to the file by both StreamWriters.

You open the streams with FileMode.Create. See the MSDN documentation (highlights by me):

Specifies that the operating system should create a new file. If the file already exists, it will be overwritten. This operation requires FileIOPermissionAccess.Write permission. System.IO.FileMode.Create is equivalent to requesting that if the file does not exist, use CreateNew; otherwise, use Truncate.

I am not sure if the second StreamWriter, depending on the order of the initialization, overwrites the file of the first StreamWriter or simply fails. Either way, they do try conflicting work.

Possible solutions:

  • Make sure the streams access the file only one after the other, e.g. by closing the first stream before the second one accesses the file, e.g. with a using block.
  • Change the FileMode on the streams so that an existing file does not get overridden if possible. (See the documentation above.)

Upvotes: 0

RobIII
RobIII

Reputation: 8821

Assuming you don't get any exceptions/errors and that basic stuff like the correct path for the csvFile FileStream is verified and found to be correct: Try adding a Flush() or propery closing the stream using Close(). Even better: use a using statement.

EDIT
After reading your question again: are you sure you just didn't switch the filestreams?

StreamWriter sw = new StreamWriter(csvFile);
StreamWriter swc = new StreamWriter(dataStruc);

as opposed to

StreamWriter sw = new StreamWriter(dataStruc);
StreamWriter swc = new StreamWriter(csvFile);

Your question and description is rather vague: "both streamwriters are used to get the same piece of information". How would stream writers be used to get information? Also: "sw streamwriter has information from file": could you be more specific? This doesn't make sense.

Whatever the case may be; use the debugger luke!

Upvotes: 2

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