File.Copy之谜

Question

I have the following code (actually divided among various methods, but this is what it amounts to):

string ThePath = FBD.SelectedPath; // FBD is a FolderBrowserDialog.
string TheSubDirPath = Path.Combine(ThePath, TheSubDirName);
if (Directory.Exists(TheSubDirPath)) {      Directory.Delete(TheSubDirPath, true); } // Want a clean, empty directory.
Directory.CreateDirectory(TheSubDirPath);
string TheSrcFileName = Path.Combine(ThePath, MyOldFileName);
string TheDestFileName = Path.Combine(TheSubDirPath, MyNewFileName);
File.Copy(TheSrcFileName, TheDestFileName, false); // Overwriting is impossible, so not needed.

This last line is causing a DirectoryNotFoundException with the message

Could not find a part of the path 'C:\\Users...\\Test01\\TheSubDirName\\MyNewFileName'."

Both the source and destination paths are exactly what I want them to be. I have tried inserting delays after the directory deletion and after the directory creation, to no effect. I have a stack trace which shows the heart of the problem

at System.IO.Error.WinIOError(Int32 errorCode, String maybeFullPath)

at System.IO.File.InternalCopy(String sourceFileName, String destFileName, Boolean overwrite, Boolean checkHost)

at System.IO.File.Copy(String sourceFileName, String destFileName, Boolean overwrite)

Any ideas?

Answer 1

Potentially there might be a situation when a result of calling the method Directory.Delete(TheSubDirPath, true) might leave the folder as 'to be removed'. So potentially, you might have removed folder after creating a new one. Try to change the statement

if (Directory.Exists(TheSubDirPath))
        Directory.Delete(TheSubDirPath, true);

with

while(Directory.Exists(TheSubDirPath))
{
    Directory.Delete(TheSubDirPath, true);
    Sleep(); //Somehow like Thread.Sleep()
}

Answer 2

replace if condition with :

if (Directory.Exists(TheSubDirPath))
    Directory.Delete(TheSubDirPath, true);