使用C#,如何删除目录中的所有文件和文件夹,但仍然保留根目录?


当前回答

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。

其他回答

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

在Windows 7中,如果您刚刚使用Windows资源管理器手动创建了它,则目录结构与以下类似:

C:
  \AAA
    \BBB
      \CCC
        \DDD

运行原始问题中建议的代码来清理目录C:\AAA,当尝试删除BBB时,行di.Delete(true)总是失败,并出现IOException“目录不是空的”。这可能是由于Windows资源管理器中的某种延迟/缓存。

以下代码对我来说工作可靠:

static void Main(string[] args)
{
    DirectoryInfo di = new DirectoryInfo(@"c:\aaa");
    CleanDirectory(di);
}

private static void CleanDirectory(DirectoryInfo di)
{
    if (di == null)
        return;

    foreach (FileSystemInfo fsEntry in di.GetFileSystemInfos())
    {
        CleanDirectory(fsEntry as DirectoryInfo);
        fsEntry.Delete();
    }
    WaitForDirectoryToBecomeEmpty(di);
}

private static void WaitForDirectoryToBecomeEmpty(DirectoryInfo di)
{
    for (int i = 0; i < 5; i++)
    {
        if (di.GetFileSystemInfos().Length == 0)
            return;
        Console.WriteLine(di.FullName + i);
        Thread.Sleep(50 * i);
    }
}

仅对File和Directory而不是FileInfo和DirectoryInfo使用静态方法将执行速度更快。(请参阅C#中File和FileInfo之间的区别是什么?)。答案显示为实用方法。

public static void Empty(string directory)
{
    foreach(string fileToDelete in System.IO.Directory.GetFiles(directory))
    {
        System.IO.File.Delete(fileToDelete);
    }
    foreach(string subDirectoryToDeleteToDelete in System.IO.Directory.GetDirectories(directory))
    {
        System.IO.Directory.Delete(subDirectoryToDeleteToDelete, true);
    }
}

我们也可以表现出对LINQ的热爱:

using System.IO;
using System.Linq;
…
var directory = Directory.GetParent(TestContext.TestDir);

directory.EnumerateFiles()
    .ToList().ForEach(f => f.Delete());

directory.EnumerateDirectories()
    .ToList().ForEach(d => d.Delete(true));

请注意,我这里的解决方案不是高性能的,因为我使用的是Get*().ToList().ForEach(…),它两次生成相同的IEnumerable。我使用扩展方法来避免此问题:

using System.IO;
using System.Linq;
…
var directory = Directory.GetParent(TestContext.TestDir);

directory.EnumerateFiles()
    .ForEachInEnumerable(f => f.Delete());

directory.EnumerateDirectories()
    .ForEachInEnumerable(d => d.Delete(true));

这是扩展方法:

/// <summary>
/// Extensions for <see cref="System.Collections.Generic.IEnumerable"/>.
/// </summary>
public static class IEnumerableOfTExtensions
{
    /// <summary>
    /// Performs the <see cref="System.Action"/>
    /// on each item in the enumerable object.
    /// </summary>
    /// <typeparam name="TEnumerable">The type of the enumerable.</typeparam>
    /// <param name="enumerable">The enumerable.</param>
    /// <param name="action">The action.</param>
    /// <remarks>
    /// “I am philosophically opposed to providing such a method, for two reasons.
    /// …The first reason is that doing so violates the functional programming principles
    /// that all the other sequence operators are based upon. Clearly the sole purpose of a call
    /// to this method is to cause side effects.”
    /// —Eric Lippert, “foreach” vs “ForEach” [http://blogs.msdn.com/b/ericlippert/archive/2009/05/18/foreach-vs-foreach.aspx]
    /// </remarks>
    public static void ForEachInEnumerable<TEnumerable>(this IEnumerable<TEnumerable> enumerable, Action<TEnumerable> action)
    {
        foreach (var item in enumerable)
        {
            action(item);
        }
    }
}

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