The following code fails to delete the file and prints file delete: so I know the file exists. With my app open I am able to delete the file in file explorer.
How can I debug this?
1) File permissions? My app created the file so should be able to delete? Regardless it would throw an exception and hit my catch debug message.
2) The file exists! According to the docs any other failure besides non-existence should be caught in my catch...
if (File.Exists(fn))
{
Debug.WriteLine("file delete: " + fn);
try
{
File.Delete(fn);
}
catch
{
Debug.WriteLine("Could not delete: " + fn);
}
} else {
Debug.WriteLine("File doesn't exist: "+fn);
}
The file is saved from a RichTextBox using the following code if this matters.
TextRange range;
FileStream fStream;
range = new TextRange(mNotepad.Document.ContentStart, mNotepad.Document.ContentEnd);
fStream = new FileStream(fn, FileMode.Create);
range.Save(fStream, DataFormats.XamlPackage);
fStream.Close();
Deleting a file does not provide a guarantee that the file will actually be removed from the file system. The file might have been opened by another process, which explicitly specified delete sharing. Very similar to read and write sharing. Also available in .NET, you'd pass FileShare.Delete to the FileStream constructor.
But the physical file can of course not be removed until all processes close the file. So it lingers beyond the File.Delete() call, can be seen by File.Exists() as well. Opening the file can no longer work, that will be rejected with access denied. Otherwise an excellent reason to never use File.Exists(), it has many problems.
If you want to find out what other process has the file opened then you can use a utility like SysInternals' Handle or Process Explorer. Expect to find back a program like a virus scanner or search indexer, could be anything however. Like a .NET program :)
From MSDN:
If the file to be deleted does not exist, no exception is thrown.
Make sure your path exists. I know you said you did, but check again.
Make sure you reach the actual File.Delete line
Cheers
I had the same issue before, follow the steps to see if it helps you. As silly as it may sound. Make sure no processes other than yours are making use of that file you created? Is this application multi-threaded? Do you have services running that use the file?
Make sure your not in debug mode, and do a Build - Clean
Check that the file is still at the location and copy the file path.
Put a break point right before file deletion.
Rebuild your project after you put your break-point.
Press F5 to debug and step through the code.
Check that the file path matches the one that you have.
I tried to reproduce similar situation with my own code
string fn = #"C:\Users\Public\Pictures\Sample Pictures\Desert - Copy.jpg";
//The file is locked by Image.FromFile
Image img = Image.FromFile(fn);
//If img.Dispose() here, then file is unlocked and can be deleted
if (File.Exists(fn))
{
try
{
File.Delete(fn);
Debug.WriteLine("file delete: " + fn);
}
catch
{
//Caught
Debug.WriteLine("Could not delete: " + fn);
}
}
else
{
Debug.WriteLine("File doesn't exist: " + fn);
}
I found the file is locked by Image.FromFile() and therefore Could not delete.
For the same reason, I believe your file with path fn is locked by the Filestream ftream
Can you try to do
fStream.Dispose();
before your delete process and rerun the program to see if you can delete the file? thanks. You can dispose the fstream and create a new one if needed,right?
Related
Every time I save a file and delete it right away using the function below, I keep getting this error message: "System.IO.IOException: The process cannot access the file because it is being used by another process".
Waiting for a couple of minutes or closing visual studio seems to only unlock the files that you uploaded previously.
public static bool DeleteFiles(List<String> paths)
{ // Returns true on success
try
{
foreach (var path in paths)
{
if (File.Exists(HostingEnvironment.MapPath("~") + path))
File.Delete(HostingEnvironment.MapPath("~") + path);
}
}
catch (Exception ex)
{
return false;
}
return true;
}
I think that the way I'm saving the files may cause them to be locked. This is the code for saving the file:
if (FileUploadCtrl.HasFile)
{
filePath = Server.MapPath("~") + "/Files/" + FileUploadCtrl.FileName;
FileUploadCtrl.SaveAs(filePath)
}
When looking for an answer I've seen someone say that you need to close the streamReader but from what I understand the SaveAs method closes and disposes automatically so I really have no idea whats causing this
After some testing, I found the problem. turns out I forgot about a function I made that was called every time I saved a media file. the function returned the duration of the file and used NAudio.Wave.WaveFileReader and NAudio.Wave.Mp3FileReader methods which I forgot to close after I called them
I fixed these issues by putting those methods inside of a using statement
Here is the working function:
public static int GetMediaFileDuration(string filePath)
{
filePath = HostingEnvironment.MapPath("~") + filePath;
if (Path.GetExtension(filePath) == ".wav")
using (WaveFileReader reader = new WaveFileReader(filePath))
return Convert.ToInt32(reader.TotalTime.TotalSeconds);
else if(Path.GetExtension(filePath) == ".mp3")
using (Mp3FileReader reader = new Mp3FileReader(filePath))
return Convert.ToInt32(reader.TotalTime.TotalSeconds);
return 0;
}
The moral of the story is, to check if you are opening the file anywhere else in your project
I think that the problem is not about streamReader in here.
When you run the program, your program runs in a specific folder. Basically, That folder is locked by your program. In that case, when you close the program, it will be unlocked.
To fix the issue, I would suggest to write/delete/update to different folder.
Another solution could be to check file readOnly attribute and change this attribute which explained in here
Last solution could be using different users. What I mean is that, if you create a file with different user which not admin, you can delete with Admin user. However, I would definitely not go with this solution cuz it is too tricky to manage different users if you are not advance windows user.
I'm writing this Windows Form Application in Visual Studio 2010 using C#.
There is a Execute button on the form, the user will hit the button, the program will generate some files and are stored in the Output folder (which is created by the program using Directory.CreateDirectory())
I want to create an Archive folder to save the output files from previous runs.
In the beginning of each run, I try to move the existing Output folder to the Archive folder, then create a new Output folder. Below is the function I ran to move directory.
static void moveToArchive()
{
if (!Directory.Exists("Archive")) Directory.CreateDirectory("Archive");
string timestamp = DateTime.Now.ToString("yyyyMMddHHmms");
try
{
Directory.Move("Output", "Archive\\" + timestamp);
}
catch(Exception e)
{
Console.WriteLine("Can not move folder: " + e.Message);
}
}
The problem I ran into confuses me a lot...
There are some times that I can successfully move the Output folder to archive, but sometimes it fails.
The error message I got from catching the exception is Access to path 'Output' is denied.
I have checked that all the files in the Output folder are not in use. I don't understand how access is denied sometimes and not all the times.
Can someone explain to me and show me how to resolve the problem?
--Edit--
After HansPassant comment, I modified the function a little to get the current directory and use the full path. However, I'm still having the same issue.
The function now looks like this:
static void moveToArchive()
{
string currentDir = Environment.CurrentDirectory;
Console.WriteLine("Current Directory = " + currentDir);
if (!Directory.Exists(currentDir + "\\Archive")) Directory.CreateDirectory(currentDir + "\\Archive");
string timestamp = DateTime.Now.ToString("yyyyMMddHHmms");
try
{
Directory.Move(currentDir + "\\Output", currentDir + "\\Archive\\" + timestamp);
}
catch(Exception e)
{
Console.WriteLine("Can not move folder: " + e.Message);
}
}
I printed out the current directory and it is just as what I was expecting, and I'm still having trouble using full path. Access to path 'C:\Users\Me\Desktop\FormApp\Output' is denied.
--Edit--
Thank you everyone for answering and commenting.
I think some of you miss this part so I'm going stress it a bit more.
The Directory.Move() sometimes work and sometimes fails.
When the function succeed, there was no problem. Output folder is moved to Archive
When the function fails, the exception message I got was Access to path denied.
Thank you all for the replies and help. I have figured out what the issue was.
It is because there was a file that's not completely closed.
I was checking the files that were generated, and missed the files the program was reading from.
All files that were generated were closed completely. It was one file I used StreamReader to open but didn't close. I modified the code and am now not having problem, so I figure that's were the issue was.
Thanks for all the comments and answers, that definitely help me with thinking and figuring out the problem.
See http://windowsxp.mvps.org/processlock.htm
Sometimes, you try to move or delete a file or folder and receive access violation or file in use - errors. To successfully delete a file, you will need to identify the process which has locked the file. You need to exit the process first and then delete the particular file. To know which process has locked a file, you may use one of the methods discussed in this article.
Using Process Explorer - download from http://download.sysinternals.com/files/ProcessExplorer.zip
Process Explorer shows you information about which handles and DLLs processes have opened or loaded.
Download Process Explorer from Microsoft site and run the program.
Click the Find menu, and choose Find Handle or DLL...
Type the file name (name of the file which is locked by some process.)
After typing the search phrase, click the Search button
You should see the list of applications which are accessing the file.
I bumped on the same problem recently. Using PE I'd figured that only process using that particular directory was explorer.exe. I'd opened few windows with explorer, one pointing to parent directory of one that I was about to move.
It appeared, that after I visited that sub-folder and then returned (even to root level!) the handle was still being kept by explorer, so C# was not able to modify it in any way (changing flags, attributes etc.).
I had to kill that explorer window in order to made C# operate properly.
File.SetAttributes(Application.dataPath + "/script", FileAttributes.Normal);
Directory.Move(Application.dataPath + "/script", Application.dataPath + "/../script");
This fixed my problem.
Try this:
If this does not solve, maybe check/change the antivirus, or the some other program is locking some file in or the folder.
static object moveLocker = new object();
static void moveToArchive()
{
lock (moveLocker)
{
System.Threading.Thread.Sleep(2000); // Give sometime to ensure all file are closed.
//Environment.CurrentDirectory = System.AppDomain.CurrentDomain.BaseDirectory;
string applicationPath = System.AppDomain.CurrentDomain.BaseDirectory;
string archiveBaseDirectoryPath = System.IO.Path.Combine(applicationPath, "Archive");
if (!Directory.Exists(archiveBaseDirectoryPath)) Directory.CreateDirectory(archiveBaseDirectoryPath);
String timestamp = DateTime.Now.ToString("yyyyMMddHHmms");
String outputDirectory = System.IO.Path.Combine(Environment.CurrentDirectory, "Output");
String destinationTS = System.IO.Path.Combine(archiveBaseDirectoryPath, timestamp);
try
{
Directory.Move(outputDirectory, destinationTS);
}
catch (Exception ex)
{
Console.WriteLine("Can not move folder " + outputDirectory + " to: " + destinationTS + "\n" + ex.Message);
}
}
}
I had the same problem, it failed sometimes but not all the time. I thought I'd wrap it in a Try Catch block and present the user with an Access Denied message and once I wrapped it in the Try Catch block it stopped failing. I can't explain why.
If existingFile.FileName <> newFileName Then
Dim dir As New IO.DirectoryInfo(existingFile.FilePath)
Dim path As String = System.IO.Path.GetDirectoryName(dir.FullName)
newFileName = path & "\" & newFileName
File.SetAttributes(existingFile.FilePath, FileAttributes.Normal)
Try
IO.File.Move(existingFile.FilePath, newFileName)
Catch ex As Exception
End Try
End If
I had a similar problem. Renamed many directories in a loop when following the certain template. From time to time the program crashed on different directories. It helped to add a sleep thread before Directory.Move. I need to create some delay.
But it slows down the copying process.
foreach (var currentFullDirPath in Directory.GetDirectories(startTargetFullDirectory, "*", SearchOption.AllDirectories))
{
var shortCurrentFolderName = new DirectoryInfo(currentFullDirPath).Name.ToLower();
if (shortCurrentFolderName.Contains(shortSourceDirectoryName))
{
// Add Thread.Sleep(1000);
Thread.Sleep(1000);
var newFullDirName = ...;
Directory.Move(currentFullDirPath, newFullDirName);
}
}
i have written some pdf files to a temp directory and these get displayed as a thumbnail that the user can view. when i close my form i clean up all of the files in the temp directory.
If however the user has one of the thumbnails open and then closes my application - it deletes the files and then throws an exception because the pdf is open in another process and cant be cleaned up.
I guess this is a shocking programming decision by me, but i am still a novice! How should i account for this in my code?
Thanks
You can detect if the file is in use by using code similar to below, then use that to warn the user that a file can't be deleted.
Unfortunately you can't delete a file that is in use.
public static bool IsFileInUse(string pathToFile)
{
if (!System.IO.File.Exists(pathToFile))
{
// File doesn't exist, so we know it's not in use.
return false;
}
bool inUse = false;
System.IO.FileStream fs;
try
{
fs = System.IO.File.Open(pathToFile, System.IO.FileMode.OpenOrCreate, System.IO.FileAccess.Read, System.IO.FileShare.None);
fs.Close();
}
catch (System.IO.IOException ex)
{
string exMess = ex.Message;
inUse = true;
}
return inUse;
}
You should catch that exception (in catch block you can inform user to close that file or it will not be deleted), and if the temp directory is yours you can try to delete it when application starts (or when it ends again), if its windows temp directory, then it does not matter that much
Tools like File Unlocker can release a file. However I think this could make programs depending on the file crash...
Maybe you can look up how they unlock files or manage to execute the unlocker via Process.Start to unlock your file and delete it.
However if it's you blocking the file you should try and fix this in your programm. Maybe you should dispose all loaded files (filestreams etc) before trying to clean it up.
I am trying a simple move as shown below and get the following error: "The process cannot access the file because it is being used by another process." How do I fix this? Thanks.
FileInfo file1 = new FileInfo(srcFile);
if (file1.Exists)
{
FileInfo file2 = new FileInfo(destFile);
if (!file2.Exists)
{
try
{
File.Move(srcFile, destFile);
}
catch (System.IO.IOException e)
{
Console.WriteLine(e.Message);
}
}
}
The error means that the file is in use:
either by your application (you need to close the file in order to be able to move it)
or by another application. There isn't much you can do here, but retry later.
Are you creating or opening file1 from within your code? If so, you'll need to close the FileStream before attempting the move.
Check with process explorer which process holds the file open.
Use procmon to find out which process is using the file and handle the situation.
When you catch this exception, you can try calling the Windows API MoveFileEx, with the MOVEFILE_DELAY_UNTIL_REBOOT flag. This will move the file the next time you reboot; this is want installers normally do when they detect a locked file. You need to be admin or LocalSystem for this to work.
Use Unlocker to see file locks. It will help you to figure out the problem.
http://www.emptyloop.com/unlocker/
maybe open the file1 in your code before you move it and don't close the filestream
I'm getting a Unauthorized Access Exception
in a file which I can delete manually.
in a folder where I'm able to delete by code other files
and the file isn't marked as read only
besides, I'm using Windows XP in a standalone PC and I have not assigned any permissions to the folder or the file.
no other process is using the file
If it helps, this is the code where the exception ocurrs:
protected void DeleteImage(string imageName)
{
if (imageName != null)
{
string f = String.Format("~/Images/{0}", imageName);
f = System.Web.Hosting.HostingEnvironment.MapPath(f);
if (File.Exists(f))
{
if (f != null) File.Delete(f);
}
}
}
Why could this happen?
I encountered the same problem, and found that writing my own Directory.Delete wrapper fixed it up. This is recursive by default:
using System.IO;
public void DeleteDirectory(string targetDir)
{
File.SetAttributes(targetDir, FileAttributes.Normal);
string[] files = Directory.GetFiles(targetDir);
string[] dirs = Directory.GetDirectories(targetDir);
foreach (string file in files)
{
File.SetAttributes(file, FileAttributes.Normal);
File.Delete(file);
}
foreach (string dir in dirs)
{
DeleteDirectory(dir);
}
Directory.Delete(targetDir, false);
}
If the directory contains a read only file, it won't delete that using Directory.Delete. It's a silly implementation by MS.
I am surprised no one suggested this method on the internet, which deletes the directory without recursing through it and changing every file's attributes. Here's that:
Process.Start("cmd.exe", "/c " + #"rmdir /s/q C:\Test\TestDirectoryContainingReadOnlyFiles");
(Change a bit to not to fire a cmd window momentarily, which is available all over the internet)
If it's not read-only it's possible that it is currently in use by another process.
Checking the obvious first...
When you open the file property and take a look at its security settings. Does the user running the code (i.e. if this is ASP.NET, Network Services / Domain Service Account) has access to actually delete the file?
If it is not, then change it and try again.
Are you running as administrator when trying to delete this manually?
If you are, then that's probably why you are able to delete it manually. Try deleting it as the account running your ASP.NET (I'm assuming it is ASP.NET since you are using System.Web.Hosting.HostingEnvironment.MapPath.)
If both failed, try to see if any other process is actually currently using this file. Good tool to find out is SysInternal Process Monitor. Filter it by path containing your filename and you should see if anything is using it. Terminate the process and try again.
I too faced the Same Problem but eventually came up with a Generic Approach. Below are my codes.
String pathfile = "C:\Users\Public\Documents\Filepath.txt" ;
if (!Directory.Exists(pathfile))
{
File.SetAttributes(pathfile, FileAttributes.Normal);
File.Delete(pathfile);
}
using (FileStream fs = File.Create(pathfile))
{
Byte[] info = new UTF8Encoding(true).GetBytes("What Ever Your Text is");
fs.Write(info, 0, info.Length);
File.SetAttributes(pathfile, FileAttributes.ReadOnly);
}
You, the human user, have a login with certain rights. The Web server might have a different login with different rights. A user starting with IUSR_XXXX or some such thing. Make sure that user has rights to the directory.
Without more info on the context in which you are deleting the file, I assume that the Web server user has different rights to a file than you do.