new System.IO.DirectoryInfo(@"C:\Temp").Delete(true);

 //Or

 System.IO.Directory.Delete(@"C:\Temp", true);

以下代码将清理目录，但将根目录保留在那里（递归）。

Action<string> DelPath = null;
DelPath = p =>
{
    Directory.EnumerateFiles(p).ToList().ForEach(File.Delete);
    Directory.EnumerateDirectories(p).ToList().ForEach(DelPath);
    Directory.EnumerateDirectories(p).ToList().ForEach(Directory.Delete);
};
DelPath(path);

string directoryPath = "C:\Temp";
Directory.GetFiles(directoryPath).ToList().ForEach(File.Delete);
Directory.GetDirectories(directoryPath).ToList().ForEach(Directory.Delete);

以下代码将递归清除文件夹：

private void clearFolder(string FolderName)
{
    DirectoryInfo dir = new DirectoryInfo(FolderName);

    foreach(FileInfo fi in dir.GetFiles())
    {
        fi.Delete();
    }

    foreach (DirectoryInfo di in dir.GetDirectories())
    {
        clearFolder(di.FullName);
        di.Delete();
    }
}

下面的示例显示了如何做到这一点。它首先创建一些目录和文件，然后通过Directory.Delete（topPath，true）；：

    static void Main(string[] args)
    {
        string topPath = @"C:\NewDirectory";
        string subPath = @"C:\NewDirectory\NewSubDirectory";

        try
        {
            Directory.CreateDirectory(subPath);

            using (StreamWriter writer = File.CreateText(subPath + @"\example.txt"))
            {
                writer.WriteLine("content added");
            }

            Directory.Delete(topPath, true);

            bool directoryExists = Directory.Exists(topPath);

            Console.WriteLine("top-level directory exists: " + directoryExists);
        }
        catch (Exception e)
        {
            Console.WriteLine("The process failed: {0}", e.Message);
        }
    }

它取自https://msdn.microsoft.com/en-us/library/fxeahc5f（v=vs.110）.aspx。

我用过

Directory.GetFiles(picturePath).ToList().ForEach(File.Delete);

删除旧图片，我不需要此文件夹中的任何对象