C# Cutting Files and Pasting in New Directory

Question

I am trying to cut files from one directory on my computer and paste it into a new directory every time a file is created in this specific directory. I am already watching the directory would it be something simple like

if (e.ChangeType == System.IO.WatcherChangeTypes.Created)
{ 
    //cut file
    //paste into new directory            
}

Answer 1

indeed, cut + paste is equivalent to move, so System.IO.File.MoveTo() should handle your problem quite well

Answer 2

First a clarification, "cut and paste" are user interface terms. In the file system, it's referred to as "moving" the file.

Second, the suggestions to use File.MoveTo may not work as you would like. The IO Watcher will tell you when a file is first created, not when it is done being written to. If you immediately move a file, you may yank it out from underneath the writer. This could result in an error in the program which is writing to the file.

The correct way to do what you are proposing is to wait until the file has been closed by the process that is writing to it, and then move it.

Have a look at the LockFileEx method in MSDN. You can use it to block until you have an exclusive lock on the file (which will happen when the writing process closes the file). Then move the file before releasing the lock.

Finally, you probably don't want to call LockFileEx from within the file system watcher callback. You may have to wait a very long time before you get the exclusive lock on the file. Instead you should queue the created files to be locked and moved by a secondary thread (or the thread pool).