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

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

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

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

其他回答

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);
        }
    }
}
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()。

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

要删除文件夹,这是使用文本框的代码和使用System.IO;的按钮:

private void Deletebt_Click(object sender, EventArgs e)
{
    System.IO.DirectoryInfo myDirInfo = new DirectoryInfo(@"" + delete.Text);

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

在我的情况下

var PhotoFile = _context.Records.Where(x => id_or_ids.Contains(x.Id)).Select(x => x.Photo).ToList();

            System.IO.DirectoryInfo di = new DirectoryInfo("wwwroot/uploads");

            foreach (FileInfo file in di.GetFiles())
            {
                if (PhotoFile.IndexOf(file.Name) != -1)
                {
                    file.Delete();
                }
            }