System.IO.File.ReadAllLines() : File already in use

Question

_{Wednesday, March 25, 2009 6:34 PM}

Hi,

I'm trying to open a file using the System.IO.File.ReadAllLines() method.

But when I try to run it, I get the following error :

System.IO.IOException :
The process cannot access the file 'c:\..' because it is being used by another process.

Ok, but i just need to read its contents, I don't need to modify it.  Is there a way I can open it in read only mode even if its locked by another process.  After all, I can open it with notepad, so there must be a way to read its content!

Thanks

Daniel

All replies (8)

_{Wednesday, March 25, 2009 9:04 PM ✅Answered | 2 votes}

Solution found...  I needed to add a FileShare.ReadWrite on the Stream.  Works like a charm now...

_{Wednesday, March 25, 2009 7:00 PM}

Try the StreamReader object I don't think it cares if it is open or not. You will still want to catch any exceptions so you can exit gracefully if the file is locked.

_{Wednesday, March 25, 2009 7:13 PM}

Unfortunately, I get the exact same error with that line of code :

System.IO.FileStream fs = new System.IO.FileStream(txtFilePath.Text, System.IO.FileMode.Open, System.IO.FileAccess.Read);

_{Wednesday, March 25, 2009 7:19 PM}

That means that the file has been locked even for reading by the process that opened it. Other than shadow copying or doing something like Unlocker does, I don't know that there is a way around that.

_{Wednesday, March 25, 2009 8:49 PM}

What do you mean by "shadow copying?"  A copy of the file on the hard drive? 

How come any other program like NotePad, TextPad, PSPad can open it then?  There must be a way to do it :/

Daniel

_{Wednesday, March 25, 2009 9:15 PM}

I'm glad you found it, I didn't read your construction code thouroughly enough. Sorry.

_{Wednesday, March 25, 2009 10:10 PM}

Hang on one sec. One moment you had this problem with File.ReadAllLines() and you solved it with using a StreamReader to iterate through the file line by line?

Yes, I know that will solve the issue, particularly if you surrounded the StreamReader with a using block, but that really is a bandaid to determine what caused the problem in the first place.

Were you doing other IO stuff before you called File.ReadAllLines()?

John Grove - TFD Group, Senior Software Engineer, EI Division, http://www.tfdg.com

_{Friday, November 9, 2012 4:24 AM}

Use FileAccess.ReadWrite, it will work.