使用字节复制文件+进度条

Question

I'm trying to put a progress on my file copy form, got that to work but the progress bar updates based on the number of files. Problem is that there are a lot of small files, and some really big ones that need to be copied.

So I'd like to know if instead of using the file number, if there's a way to check the number of bytes being written instead. Any suggestions are much appreciated. Here is the code I have now:

    private void BackgroundWorker_DoWork(object sender, DoWorkEventArgs e)
    {
        string SourcePath = RegistryRead.ReadOriginalPath();
        string DestinationPath = RegistryRead.ReadNewPath();

        if (Directory.Exists(SourcePath))
        {
            //Now Create all of the directories 
            string[] allDirectories = Directory.GetDirectories(SourcePath, "*", SearchOption.AllDirectories);
            string[] allFiles = Directory.GetFiles(SourcePath, "*.*", SearchOption.AllDirectories);
            int numberOfItems = allDirectories.Length + allFiles.Length;
            int progress = 0;

            foreach (string dirPath in allDirectories)
            {
                Directory.CreateDirectory(dirPath.Replace(SourcePath, DestinationPath));
                progress++;
                BackgroundWorker.ReportProgress(100 * progress / numberOfItems);
            }

            //Copy all the files 
            foreach (string newPath in allFiles)
            {
                File.Copy(newPath, newPath.Replace(SourcePath, DestinationPath));
                progress++;
                BackgroundWorker.ReportProgress(100 * progress / numberOfItems);
            }
        }

    }

    private void backgroundWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
    {
        // Change the value of the ProgressBar to the BackgroundWorker progress.
        progressBar1.Value = e.ProgressPercentage;
    }

Thanks in advance

Answer 1

If you want to do this yourself you can

1. Iterate over all files counting the total size to be copied.
2. Call CopyFileEx to do the copying. This uses a callback mechanism to report progress and that callback includes the number of bytes copied for the current file.
3. Keep track of how many bytes have been copied in total and use that to report an overall progress.

There is quite possibly a .net managed equivalent to CopyFileEx.

However, I would recommend calling SHFileOperation and let the system do the hard work for you. As you are discovering this task is exceedingly hard to do well. As an added benefit of using the shell to do the work, you'll get the standard system dialog.

Answer 2

You will need to implement your own file copying code, and report the progress from there.

EDIT: In case you don't want to copy the files yourself, you could start another background worker that will check the file copy progress (get the properties of the currently copied file, and check its length). If you don't run into sharing issues, it will provide you with the information you need to update the progress bar.