子文件夹不被复制

我正在使用此SO帖子的函数将文件夹内容复制到另一个文件夹，但它不复制子文件夹及其内容。

private static void DirectoryCopy(string sourceDirName, string destDirName, bool copySubDirs)
{
    DirectoryInfo dir = new DirectoryInfo(sourceDirName);
    DirectoryInfo[] dirs = dir.GetDirectories();
    // If the source directory does not exist, throw an exception.
    if (!dir.Exists)
    {
        throw new DirectoryNotFoundException(
            "Source directory does not exist or could not be found: "
            + sourceDirName);
    }
    // If the destination directory does not exist, create it.
    if (!Directory.Exists(destDirName))
    {
        Debug.Log("Directory created.." + destDirName);
        Directory.CreateDirectory(destDirName);
    }
    // Get the file contents of the directory to copy.
    FileInfo[] files = dir.GetFiles();
    foreach (FileInfo file in files)
    {
        // Create the path to the new copy of the file.
        string temppath = Path.Combine(destDirName, file.Name);
        // Copy the file.
        file.CopyTo(temppath, false);
    }
    // If copySubDirs is true, copy the subdirectories.
    if (copySubDirs)
    {
        foreach (DirectoryInfo subdir in dirs)
        {
            // Create the subdirectory.
            string temppath = Path.Combine(destDirName, subdir.Name);
            // Copy the subdirectories.
            DirectoryCopy(subdir.FullName, temppath, copySubDirs);
        }
    }
}

它的名字是这样的:

string destingationPath = startupFolder + @"'NetworkingDemoPlayerWithNetworkAwareShooting1_Data";
DirectoryCopy("NetworkingDemoPlayerWithNetworkAwareShooting1_Data", destingationPath, true);