只是想加上我的版本。它可以处理目录和文件，如果目标文件存在，则可以覆盖或跳过。

public static void Copy(
    string source,
    string destination,
    string pattern = "*",
    bool includeSubFolders = true,
    bool overwrite = true,
    bool overwriteOnlyIfSourceIsNewer = false)
{
    if (File.Exists(source))
    {
        // Source is a file, copy and leave
        CopyFile(source, destination);
        return;
    }

    if (!Directory.Exists(source))
    {
        throw new DirectoryNotFoundException($"Source directory does not exists: `{source}`");
    }

    var files = Directory.GetFiles(
        source,
        pattern,
        includeSubFolders ?
            SearchOption.AllDirectories :
            SearchOption.TopDirectoryOnly);

    foreach (var file in files)
    {
        var newFile = file.Replace(source, destination);
        CopyFile(file, newFile, overwrite, overwriteOnlyIfSourceIsNewer);
    }
}

private static void CopyFile(
    string source,
    string destination,
    bool overwrite = true,
    bool overwriteIfSourceIsNewer = false)
{
    if (!overwrite && File.Exists(destination))
    {
        return;
    }

    if (overwriteIfSourceIsNewer && File.Exists(destination))
    {
        var sourceLastModified = File.GetLastWriteTimeUtc(source);
        var destinationLastModified = File.GetLastWriteTimeUtc(destination);
        if (sourceLastModified <= destinationLastModified)
        {
            return;
        }

        CreateDirectory(destination);
        File.Copy(source, destination, overwrite);
        return;
    }

    CreateDirectory(destination);
    File.Copy(source, destination, overwrite);
}

private static void CreateDirectory(string filePath)
{
    var targetDirectory = Path.GetDirectoryName(filePath);
    if (targetDirectory != null && !Directory.Exists(targetDirectory))
    {
        Directory.CreateDirectory(targetDirectory);
    }
}

你可以一直使用这个，摘自微软网站。

static void Main()
{
    // Copy from the current directory, include subdirectories.
    DirectoryCopy(".", @".\temp", true);
}

private static void DirectoryCopy(string sourceDirName, string destDirName, bool copySubDirs)
{
    // Get the subdirectories for the specified directory.
    DirectoryInfo dir = new DirectoryInfo(sourceDirName);

    if (!dir.Exists)
    {
        throw new DirectoryNotFoundException(
            "Source directory does not exist or could not be found: "
            + sourceDirName);
    }

    DirectoryInfo[] dirs = dir.GetDirectories();
    // If the destination directory doesn't exist, create it.
    if (!Directory.Exists(destDirName))
    {
        Directory.CreateDirectory(destDirName);
    }

    // Get the files in the directory and copy them to the new location.
    FileInfo[] files = dir.GetFiles();
    foreach (FileInfo file in files)
    {
        string temppath = Path.Combine(destDirName, file.Name);
        file.CopyTo(temppath, false);
    }

    // If copying subdirectories, copy them and their contents to new location.
    if (copySubDirs)
    {
        foreach (DirectoryInfo subdir in dirs)
        {
            string temppath = Path.Combine(destDirName, subdir.Name);
            DirectoryCopy(subdir.FullName, temppath, copySubDirs);
        }
    }
}

如果您喜欢Konrad的流行答案，但希望源代码本身是目标文件夹下的一个文件夹，而不是将它的子文件夹放在目标文件夹下，下面是实现该目的的代码。它返回新创建的DirectoryInfo，这很方便:

public static DirectoryInfo CopyFilesRecursively(DirectoryInfo source, DirectoryInfo target)
{
  var newDirectoryInfo = target.CreateSubdirectory(source.Name);
  foreach (var fileInfo in source.GetFiles())
    fileInfo.CopyTo(Path.Combine(newDirectoryInfo.FullName, fileInfo.Name));

  foreach (var childDirectoryInfo in source.GetDirectories())
    CopyFilesRecursively(childDirectoryInfo, newDirectoryInfo);

  return newDirectoryInfo;
}

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。

下面的代码是微软建议如何复制目录 由亲爱的@iato分享 但是它只是递归地复制源文件夹的子目录和文件，而不复制源文件夹本身(如右键单击->复制)。

但在这个答案下面有一个棘手的方法:

private static void DirectoryCopy(string sourceDirName, string destDirName, bool copySubDirs = true)
        {
            // Get the subdirectories for the specified directory.
            DirectoryInfo dir = new DirectoryInfo(sourceDirName);

            if (!dir.Exists)
            {
                throw new DirectoryNotFoundException(
                    "Source directory does not exist or could not be found: "
                    + sourceDirName);
            }

            DirectoryInfo[] dirs = dir.GetDirectories();
            // If the destination directory doesn't exist, create it.
            if (!Directory.Exists(destDirName))
            {
                Directory.CreateDirectory(destDirName);
            }

            // Get the files in the directory and copy them to the new location.
            FileInfo[] files = dir.GetFiles();
            foreach (FileInfo file in files)
            {
                string temppath = Path.Combine(destDirName, file.Name);
                file.CopyTo(temppath, false);
            }

            // If copying subdirectories, copy them and their contents to new location.
            if (copySubDirs)
            {
                foreach (DirectoryInfo subdir in dirs)
                {
                    string temppath = Path.Combine(destDirName, subdir.Name);
                    DirectoryCopy(subdir.FullName, temppath, copySubDirs);
                }
            }
        }

如果你想递归复制源文件夹和子文件夹的内容，你可以像这样简单地使用它:

string source = @"J:\source\";
string dest= @"J:\destination\";
DirectoryCopy(source, dest);

但是如果你想复制源目录自己(类似于你右键单击源文件夹，然后单击复制，然后在目标文件夹中单击粘贴)，你应该像这样使用:

 string source = @"J:\source\";
 string dest= @"J:\destination\";
 DirectoryCopy(source, Path.Combine(dest, new DirectoryInfo(source).Name));

使用这个类。

public static class Extensions
{
    public static void CopyTo(this DirectoryInfo source, DirectoryInfo target, bool overwiteFiles = true)
    {
        if (!source.Exists) return;
        if (!target.Exists) target.Create();

        Parallel.ForEach(source.GetDirectories(), (sourceChildDirectory) => 
            CopyTo(sourceChildDirectory, new DirectoryInfo(Path.Combine(target.FullName, sourceChildDirectory.Name))));

        foreach (var sourceFile in source.GetFiles())
            sourceFile.CopyTo(Path.Combine(target.FullName, sourceFile.Name), overwiteFiles);
    }
    public static void CopyTo(this DirectoryInfo source, string target, bool overwiteFiles = true)
    {
        CopyTo(source, new DirectoryInfo(target), overwiteFiles);
    }
}