How to rename a folder in c# which is currently opened by windows explorer

Question

When renaming a folder in C#, System.IO.Directory.Move throws System.IO.IOException (message \"access denied\") if that folder or any subfolder is curr

Answer 1

I've used API Monitor v2 by Rohitab to monitor Windows API calls.

When changing the directory name from D:\test to D:\abc, this call was logged:

explorerframe.dll   ITransferSource::RenameItem ( 0x0000000015165738, "abc", TSF_COPY_CREATION_TIME | TSF_COPY_LOCALIZED_NAME | TSF_COPY_WRITE_TIME | TSF_DELETE_RECYCLE_IF_POSSIBLE, 0x00000000150f77d0 )

Digging further into the output of the monitor shows some native calls:

As you can see, they're not using MoveFile, instead, they use NtOpenFile with FILE_OPEN_FOR_BACKUP_INTENT and others to open the original directory, then call NtSetInformationFile with the new directory name and the flag FileRenameInformation which is documented here.

Unfortunately, these are all kernel calls.

You can get a handle to a directory in C/C++ from user-mode like this:

HANDLE h = ::CreateFileA("D:\\test",
    DELETE | FILE_READ_ATTRIBUTES | SYNCHRONIZE,
    FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
    OPEN_EXISTING,
    FILE_FLAG_BACKUP_SEMANTICS,
    NULL);

But then, you still need a user-mode alternative for the NtSetInformationFile-call.

Some options to proceed (ordered by complexity):

• See if you can use the shell interface ITransferSource::RenameItem or find a ready-to-use shell function
• Dig further into the user-mode solution and try to find an alternative to NtSetInformationFile
• Write a driver that contains a IOCTL that does these kernel-mode stuff and call DeviceIoControl from C#.

Update

Seems like the SHFileOperation function does all of the above as found by the OP.

Will leave this answer online, because it might show others how to debug similar problems and get valuable pointers.