How to delete any dynamically created file from solution?

I am creating a file into the solution's directory as below:

var targetPathToCreate = Path.Combine(HttpRuntime.AppDomainAppPath, "FolderName");

DirectoryInfo dirInfo = new DirectoryInfo(targetPathToCreate);

if (!dirInfo.Exists)
{
    dirInfo.Create();
}

var filePath = Path.Combine(targetPathToCreate, "FileName");
System.IO.File.WriteAllBytes(filePath, bytesArray);

and further I am sending this document via email and then trying to delete this document.

For that I tried this code:

System.IO.File.Delete("FilePath");

but this line throws an exception:

The process cannot access the file because it is being used by another process

Is there any way to delete the files by overcoming the exception?

Solution

You can use garbage collector's WaitForPendingFinalizers function. It will suspend the current thread until the thread that is processing the queue of finalizers has emptied that queue.

   if (System.IO.File.Exists(filePath))
    {
      System.GC.Collect();
      System.GC.WaitForPendingFinalizers();
      System.IO.File.Delete(filePath);
    }

If this doesn't work, you have to dispose your mail object.

mail.Attachments.Add(...);
smtpServer.Send(mail);
mail.Dispose();
System.IO.File.Delete(filePath);