这个网站总是帮助我很多，现在轮到我用我所知道的帮助其他人了。

我希望我下面的代码对某些人有用。

string source_dir = @"E:\";
string destination_dir = @"C:\";

// substring is to remove destination_dir absolute path (E:\).

// Create subdirectory structure in destination    
    foreach (string dir in System.IO.Directory.GetDirectories(source_dir, "*", System.IO.SearchOption.AllDirectories))
    {
        System.IO.Directory.CreateDirectory(System.IO.Path.Combine(destination_dir, dir.Substring(source_dir.Length + 1)));
        // Example:
        //     > C:\sources (and not C:\E:\sources)
    }

    foreach (string file_name in System.IO.Directory.GetFiles(source_dir, "*", System.IO.SearchOption.AllDirectories))
    {
        System.IO.File.Copy(file_name, System.IO.Path.Combine(destination_dir, file_name.Substring(source_dir.Length + 1)));
    }

对于d4nt的答案有一个小的改进，因为如果你在服务器和开发机器上工作，你可能想检查错误，而不必更改xcopy路径:

public void CopyFolder(string source, string destination)
{
    string xcopyPath = Environment.GetEnvironmentVariable("WINDIR") + @"\System32\xcopy.exe";
    ProcessStartInfo info = new ProcessStartInfo(xcopyPath);
    info.UseShellExecute = false;
    info.RedirectStandardOutput = true;
    info.Arguments = string.Format("\"{0}\" \"{1}\" /E /I", source, destination);

    Process process = Process.Start(info);
    process.WaitForExit();
    string result = process.StandardOutput.ReadToEnd();

    if (process.ExitCode != 0)
    {
        // Or your own custom exception, or just return false if you prefer.
        throw new InvalidOperationException(string.Format("Failed to copy {0} to {1}: {2}", source, destination, result));
    }
}

复制并替换文件夹中的所有文件

        public static void CopyAndReplaceAll(string SourcePath, string DestinationPath, string backupPath)
    {
            foreach (string dirPath in Directory.GetDirectories(SourcePath, "*", SearchOption.AllDirectories))
            {
                Directory.CreateDirectory($"{DestinationPath}{dirPath.Remove(0, SourcePath.Length)}");
                Directory.CreateDirectory($"{backupPath}{dirPath.Remove(0, SourcePath.Length)}");
            }
            foreach (string newPath in Directory.GetFiles(SourcePath, "*.*", SearchOption.AllDirectories))
            {
                if (!File.Exists($"{ DestinationPath}{newPath.Remove(0, SourcePath.Length)}"))
                    File.Copy(newPath, $"{ DestinationPath}{newPath.Remove(0, SourcePath.Length)}");
                else
                    File.Replace(newPath
                        , $"{ DestinationPath}{newPath.Remove(0, SourcePath.Length)}"
                        , $"{ backupPath}{newPath.Remove(0, SourcePath.Length)}", false);
            }
    }

这段代码的属性:

没有并行任务，性能较差，但其思想是逐文件处理，因此可以记录或停止。 可以跳过隐藏文件 可以跳过修改日期吗 可以打破或不(您选择)对文件复制错误 SMB和FileShare使用64K的Buffer。读写避免锁 个性化您的异常消息 对于Windows

笔记 ExceptionToString()是一个个人扩展，试图获得内部异常和显示堆栈。将其替换为ex.Message或任何其他代码。 log4net。ILog _log我使用==Log4net==您可以用不同的方式创建您的日志。

/// <summary>
/// Recursive Directory Copy
/// </summary>
/// <param name="fromPath"></param>
/// <param name="toPath"></param>
/// <param name="continueOnException">on error, continue to copy next file</param>
/// <param name="skipHiddenFiles">To avoid files like thumbs.db</param>
/// <param name="skipByModifiedDate">Does not copy if the destiny file has the same or more recent modified date</param>
/// <remarks>
/// </remarks>
public static void CopyEntireDirectory(string fromPath, string toPath, bool continueOnException = false, bool skipHiddenFiles = true, bool skipByModifiedDate = true)
{
    log4net.ILog _log = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
    string nl = Environment.NewLine;

    string sourcePath = "";
    string destPath = "";
    string _exMsg = "";

    void TreateException(Exception ex)
    {
        _log.Warn(_exMsg);
        if (continueOnException == false)
        {
            throw new Exception($"{_exMsg}{nl}----{nl}{ex.ExceptionToString()}");
        }
    }

    try
    {
        foreach (string fileName in Directory.GetFileSystemEntries(fromPath, "*", SearchOption.AllDirectories))
        {
            sourcePath = fileName;
            destPath = Regex.Replace(fileName, "^" + Regex.Escape(fromPath), toPath);

            Directory.CreateDirectory(Path.GetDirectoryName(destPath));
            
            _log.Debug(FileCopyStream(sourcePath, destPath,skipHiddenFiles,skipByModifiedDate));
        }
    }
    // Directory must be less than 148 characters, File must be less than 261 characters
    catch (PathTooLongException)
    {
        throw new Exception($"Both paths must be less than 148 characters:{nl}{sourcePath}{nl}{destPath}");
    }
    // Not enough disk space. Cancel further copies
    catch (IOException ex) when ((ex.HResult & 0xFFFF) == 0x27 || (ex.HResult & 0xFFFF) == 0x70)
    {
        throw new Exception($"Not enough disk space:{nl}'{toPath}'");
    }
    // used by another process
    catch (IOException ex) when ((uint)ex.HResult == 0x80070020)
    {
        _exMsg = $"File is being used by another process:{nl}'{destPath}'{nl}{ex.Message}";
        TreateException(ex);
    }
    catch (UnauthorizedAccessException ex)
    {
        _exMsg = $"Unauthorized Access Exception:{nl}from:'{sourcePath}'{nl}to:{destPath}";
        TreateException(ex);
    }
    catch (Exception ex)
    {
        _exMsg = $"from:'{sourcePath}'{nl}to:{destPath}";
        TreateException(ex);
    }
}

/// <summary>
/// File Copy using Stream 64K and trying to avoid locks with fileshare
/// </summary>
/// <param name="sourcePath"></param>
/// <param name="destPath"></param>
/// <param name="skipHiddenFiles">To avoid files like thumbs.db</param>
/// <param name="skipByModifiedDate">Does not copy if the destiny file has the same or more recent modified date</param>
public static string FileCopyStream(string sourcePath, string destPath, bool skipHiddenFiles = true, bool skipByModifiedDate = true)
{
    // Buffer should be 64K = 65536‬ bytes 
    // Increasing the buffer size beyond 64k will not help in any circunstance,
    // as the underlying SMB protocol does not support buffer lengths beyond 64k."
    byte[] buffer = new byte[65536];

    if (!File.Exists(sourcePath))
        return $"is not a file: '{sourcePath}'";

    FileInfo sourcefileInfo = new FileInfo(sourcePath);
    FileInfo destFileInfo = null;
    if (File.Exists(destPath))
        destFileInfo = new FileInfo(destPath);

    if (skipHiddenFiles)
    {
        if (sourcefileInfo.Attributes.HasFlag(FileAttributes.Hidden))
            return $"Hidden File Not Copied: '{sourcePath}'";
    }

    using (FileStream input = sourcefileInfo.Open(FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
    using (FileStream output = new FileStream(destPath, FileMode.OpenOrCreate, FileAccess.Write, FileShare.ReadWrite, buffer.Length))
    {
        if (skipByModifiedDate && destFileInfo != null)
        {
            if (destFileInfo.LastWriteTime < sourcefileInfo.LastWriteTime)
            {
                input.CopyTo(output, buffer.Length);
                destFileInfo.LastWriteTime = sourcefileInfo.LastWriteTime;
                return $"Replaced: '{sourcePath}'";
            }
            else
            {
                return $"NOT replaced (more recent or same file): '{sourcePath}'";
            }
        }
        else
        {
            input.CopyTo(output, buffer.Length);
            destFileInfo = new FileInfo(destPath);
            destFileInfo.LastWriteTime = sourcefileInfo.LastWriteTime;
            return $"New File: '{sourcePath}'";
        }
    }
}

递归复制文件夹而不递归，以避免堆栈溢出。

public static void CopyDirectory(string source, string target)
{
    var stack = new Stack<Folders>();
    stack.Push(new Folders(source, target));

    while (stack.Count > 0)
    {
        var folders = stack.Pop();
        Directory.CreateDirectory(folders.Target);
        foreach (var file in Directory.GetFiles(folders.Source, "*.*"))
        {
            File.Copy(file, Path.Combine(folders.Target, Path.GetFileName(file)));
        }

        foreach (var folder in Directory.GetDirectories(folders.Source))
        {
            stack.Push(new Folders(folder, Path.Combine(folders.Target, Path.GetFileName(folder))));
        }
    }
}

public class Folders
{
    public string Source { get; private set; }
    public string Target { get; private set; }

    public Folders(string source, string target)
    {
        Source = source;
        Target = target;
    }
}

或者，如果你想走一条艰难的路，为你的微软项目添加一个引用。然后使用下面的代码:

Microsoft.VisualBasic.FileIO.FileSystem.CopyDirectory(fromDirectory, toDirectory);

然而，使用一个递归函数是一个更好的方法，因为它不需要加载VB dll。