I'm kinda new to working with C# .NET's System.IO namespace. So please forgive me for some basic questions.
I am writing an online interface that will allow a site owner to modify files and directories on the server.
I have gotten inconsistent performance out of System.IO.Directory.Delete(PathToDelete, true);
. Sometimes it works great, sometimes it throws an error. My controller looks like this:
public ActionResult FileDelete(List<string> entity = null)
{
if (entity != null)
{
if (entity.Count() > 0)
foreach (string s in entity)
{
string CurrentFile = s.Replace(Path.AltDirectorySeparatorChar, Path.DirectorySeparatorChar);
string FileToDelete = Server.MapPath(CurrentFile);
bool isDir = (System.IO.File.GetAttributes(FileToDelete) & FileAttributes.Directory) == FileAttributes.Directory;
if (isDir)
{
if (System.IO.Directory.Exists(FileToDelete))
{
//Problem line/////////////////////////////////
System.IO.Directory.Delete(FileToDelete, true);
}
}
else
{
if (System.IO.File.Exists(FileToDelete))
{
System.IO.File.Delete(FileToDelete);
string ThumbConfigDir = ConfigurationManager.AppSettings["ThumbnailSubdirectory"];
string ThumbFileToDelete = Path.GetDirectoryName(FileToDelete) + Path.DirectorySeparatorChar + ThumbConfigDir + Path.DirectorySeparatorChar + Path.GetFi开发者_开发技巧leName(FileToDelete);
if (System.IO.File.Exists(ThumbFileToDelete))
{
System.IO.File.Delete(ThumbFileToDelete);
}
}
}
}
}
return Redirect(HttpContext.Request.UrlReferrer.AbsoluteUri.ToString());
}
Sometimes, I get an error when tring to delete directories that says:
The directory is not empty.
Description: An unhandled exception occurred during the execution of the current
web request. Please review the stack trace for more information about the error
and where it originated in the code.
Exception Details: System.IO.IOException: The directory is not empty.
Source Error:
Line 137: if (System.IO.Directory.Exists(FileToDelete))
Line 138: {
Line 139: System.IO.Directory.Delete(FileToDelete, true);
Line 140: }
Line 141: }
I'm not sure what kind of defensive coding I can implement to avoid get errors like these. Any thoughts? Am I missunderstanding what it means to set recursive to true by saying System.IO.Directory.Delete(FileToDelete, true);
?
If there's a file that's in use, the Delete won't empty the directory, and then will fail when it will try to delete the directory.
Try using FileInfo
instead of the static methods, and use Refresh after you do any action on the file. (or DirectoryInfo for direcotries)
Similar problem
In general you just have to expect this sort of exceptions from file/folder manipulation code. There is large number of reasons why it could happen - some file in use, some process have working folder set to the directory, some files are not visible to your process due to permissions and so on.
Process monitor ( http://technet.microsoft.com/en-us/sysinternals/bb896645.aspx) likely will show what causes the problem.
One of common reason if you create folder yourself for your temporary files and then try to delete it is to forget to dispose Stream objects related to files in such folder (could be indirect links by Reader and Writer objets, XmlDocument).
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