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

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();
    }
}

其他回答

是的,这是正确的方法。如果你想给自己一个“干净”(或者,我更喜欢称之为“空”函数),你可以创建一个扩展方法。

public static void Empty(this System.IO.DirectoryInfo directory)
{
    foreach(System.IO.FileInfo file in directory.GetFiles()) file.Delete();
    foreach(System.IO.DirectoryInfo subDirectory in directory.GetDirectories()) subDirectory.Delete(true);
}

然后,这将允许您执行以下操作:。。

System.IO.DirectoryInfo directory = new System.IO.DirectoryInfo(@"C:\...");

directory.Empty();
System.IO.DirectoryInfo di = new DirectoryInfo("YourPath");

foreach (FileInfo file in di.GetFiles())
{
    file.Delete(); 
}
foreach (DirectoryInfo dir in di.GetDirectories())
{
    dir.Delete(true); 
}

如果您的目录可能有许多文件,EnumerateFiles()比GetFiles()更有效,因为当您使用EnumerateFile()时,您可以在返回整个集合之前开始枚举它,而不是GetFiles(,在开始枚举之前,您需要在内存中加载整个集合。请参阅此处的引用:

因此,当您使用许多文件和目录时,EnumerateFiles()可以更有效。

这同样适用于EnumerateDirectories()和GetDirectory()。所以代码应该是:

foreach (FileInfo file in di.EnumerateFiles())
{
    file.Delete(); 
}
foreach (DirectoryInfo dir in di.EnumerateDirectories())
{
    dir.Delete(true); 
}

对于这个问题,确实没有理由使用GetFiles()和GetDirectories()。

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);
    }
}

这是我看完所有帖子后使用的工具。确实如此

删除所有可以删除的内容如果某些文件保留在文件夹中,则返回false

它处理的是

只读文件删除延迟锁定的文件

它不使用Directory.Delete,因为该进程因异常而中止。

    /// <summary>
    /// Attempt to empty the folder. Return false if it fails (locked files...).
    /// </summary>
    /// <param name="pathName"></param>
    /// <returns>true on success</returns>
    public static bool EmptyFolder(string pathName)
    {
        bool errors = false;
        DirectoryInfo dir = new DirectoryInfo(pathName);

        foreach (FileInfo fi in dir.EnumerateFiles())
        {
            try
            {
                fi.IsReadOnly = false;
                fi.Delete();

                //Wait for the item to disapear (avoid 'dir not empty' error).
                while (fi.Exists)
                {
                    System.Threading.Thread.Sleep(10);
                    fi.Refresh();
                }
            }
            catch (IOException e)
            {
                Debug.WriteLine(e.Message);
                errors = true;
            }
        }

        foreach (DirectoryInfo di in dir.EnumerateDirectories())
        {
            try
            {
                EmptyFolder(di.FullName);
                di.Delete();

                //Wait for the item to disapear (avoid 'dir not empty' error).
                while (di.Exists)
                {
                    System.Threading.Thread.Sleep(10);
                    di.Refresh();
                }
            }
            catch (IOException e)
            {
                Debug.WriteLine(e.Message);
                errors = true;
            }
        }

        return !errors;
    }

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);
        }
    }
}