如何在 C# 中删除包含只读文件的目录？

Question

我需要删除一个包含只读文件的目录。哪种方法更好：

• 使用DirectoryInfo.Delete()，或者，

• ManagementObject.InvokeMethod("Delete")?

使用DirectoryInfo.Delete()，我必须手动关闭每个文件的只读属性，但ManagementObject.InvokeMethod("Delete") 似乎不需要。有没有一种情况比另一种更可取？

示例代码（test.txt 是只读的）。

第一种方式：

DirectoryInfo dir = new DirectoryInfo(@"C:\Users\David\Desktop\");
dir.CreateSubdirectory("Test");

DirectoryInfo test = new DirectoryInfo(@"C:\Users\David\Desktop\Test\");
File.Copy(@"C:\Users\David\Desktop\test.txt", @"C:\Users\David\Desktop\Test\test.txt");
File.SetAttributes(@"C:\Users\David\Desktop\Test\test.txt", FileAttributes.Archive);
test.Delete(true);

第二种方式：

DirectoryInfo dir = new DirectoryInfo(@"C:\Users\David\Desktop\");
dir.CreateSubdirectory("Test");

DirectoryInfo test = new DirectoryInfo(@"C:\Users\David\Desktop\Test\");
File.Copy(@"C:\Users\David\Desktop\test.txt", @"C:\Users\David\Desktop\Test\test.txt");

string folder = @"C:\Users\David\Desktop\Test";
string dirObject = "Win32_Directory.Name='" + folder + "'";
using (ManagementObject managementObject = new ManagementObject(dirObject))
{
    managementObject.Get();
    ManagementBaseObject outParams = managementObject.InvokeMethod("Delete", null,
    null);
    // ReturnValue should be 0, else failure
    if (Convert.ToInt32(outParams.Properties["ReturnValue"].Value) != 0)
    {
    }
}

Answer 1

我会说你的第一种方法看起来更明确和可读。第二种方法闻起来像反射，不是类型安全的，而且看起来很奇怪。 ManagementObject 可以代表多个东西，所以.InvokeMethod("Delete") 实际删除一个目录并不明显。

Answer 2

最好的解决办法是将所有文件标记为非只读，然后删除目录。

// delete/clear hidden attribute
File.SetAttributes(filePath, File.GetAttributes(filePath) & ~FileAttributes.Hidden);

// delete/clear archive and read only attributes
File.SetAttributes(filePath, File.GetAttributes(filePath) 
    & ~(FileAttributes.Archive | FileAttributes.ReadOnly));

请注意，~ 是一个按位逻辑运算符，它返回给定二进制值的补码。我没有对此进行测试，但它应该可以工作。

谢谢！

Answer 3

这是一个扩展方法，它将Attributes递归设置为Normal，然后删除项目：

public static void DeleteReadOnly(this FileSystemInfo fileSystemInfo)
{
    var directoryInfo = fileSystemInfo as DirectoryInfo;    
    if (directoryInfo != null)
    {
        foreach (FileSystemInfo childInfo in directoryInfo.GetFileSystemInfos())
        {
            childInfo.DeleteReadOnly();
        }
    }

    fileSystemInfo.Attributes = FileAttributes.Normal;
    fileSystemInfo.Delete();
}

Answer 4

从表面上看，使用 WMI 方法似乎比遍历整个文件系统更有效（例如，假设该目录有成千上万个文件）。但我不知道 WMI 也不进行迭代。如果是这样，那么更接近金属（同样，假设）应该更有效。

为了优雅，我承认递归方法很酷。

性能测试应该回答效率问题。如果包装在 DirectoryInfo 的扩展方法中，两者都可以很优雅。

Answer 5

另一种不需要递归的方法。

public static void ForceDeleteDirectory(string path)
{
    DirectoryInfo root;
    Stack<DirectoryInfo> fols;
    DirectoryInfo fol;
    fols = new Stack<DirectoryInfo>();
    root = new DirectoryInfo(path);
    fols.Push(root);
    while (fols.Count > 0)
    {
        fol = fols.Pop();
        fol.Attributes = fol.Attributes & ~(FileAttributes.Archive | FileAttributes.ReadOnly | FileAttributes.Hidden);
        foreach (DirectoryInfo d in fol.GetDirectories())
        {
            fols.Push(d);
        }
        foreach (FileInfo f in fol.GetFiles())
        {
            f.Attributes = f.Attributes & ~(FileAttributes.Archive | FileAttributes.ReadOnly | FileAttributes.Hidden);
            f.Delete();
        }
    }
    root.Delete(true);
}

Answer 6

试试这个，

private void DeleteRecursiveFolder(string pFolderPath)
{
    foreach (string Folder in Directory.GetDirectories(pFolderPath))
    {
        DeleteRecursiveFolder(Folder);
    }

    foreach (string file in Directory.GetFiles(pFolderPath))
    {
        var pPath = Path.Combine(pFolderPath, file);
        FileInfo fi = new FileInfo(pPath);
        File.SetAttributes(pPath, FileAttributes.Normal);
        File.Delete(file);
    }

    Directory.Delete(pFolderPath);
}

Answer 7

private void DeleteRecursiveFolder(DirectoryInfo dirInfo)
{
    foreach (var subDir in dirInfo.GetDirectories())
    {
        DeleteRecursiveFolder(subDir);
    }

    foreach (var file in dirInfo.GetFiles())
    {
        file.Attributes=FileAttributes.Normal;
        file.Delete();
    }

    dirInfo.Delete();
}

Answer 8

这是另一种避免自身递归的解决方案。

public static void DirectoryDeleteAll(string directoryPath)
{
    var rootInfo = new DirectoryInfo(directoryPath) { Attributes = FileAttributes.Normal };
    foreach (var fileInfo in rootInfo.GetFileSystemInfos()) fileInfo.Attributes = FileAttributes.Normal;
    foreach (var subDirectory in Directory.GetDirectories(directoryPath, "*", SearchOption.AllDirectories))
    {
        var subInfo = new DirectoryInfo(subDirectory) { Attributes = FileAttributes.Normal };
        foreach (var fileInfo in subInfo.GetFileSystemInfos()) fileInfo.Attributes = FileAttributes.Normal;
    }
    Directory.Delete(directoryPath, true);
}

这通过在删除之前重置文件夹和文件的属性来工作，因此您可以删除“DirectoryResetAttributes”方法的最后一行并单独使用删除。

在相关说明中，虽然这有效，但我在删除“太长”的路径时遇到了问题，最终使用了此处发布的 robocopy 解决方案：C# deleting a folder that has long paths

Answer 9

避免递归调用的最简单方法是在获取FileSystemInfos 时使用AllDirectories 选项，如下所示：

public static void ForceDeleteDirectory(string path) 
{
    var directory = new DirectoryInfo(path) { Attributes = FileAttributes.Normal };

    foreach (var info in directory.GetFileSystemInfos("*", SearchOption.AllDirectories))
    {
        info.Attributes = FileAttributes.Normal;
    }

    directory.Delete(true);
}

Answer 10

为了跟进 Vitaliy Ulantikov 的解决方案，我用重命名/移动文件夹方法对其进行了补充：

  public static void renameFolder(String sourcePath, String targetPath) {
     try
     {
        if (System.IO.Directory.Exists(targetPath))
           DeleteFileSystemInfo(new DirectoryInfo(targetPath));
        System.IO.Directory.Move(sourcePath, targetPath);
     }
     catch (Exception ex)
     {
        Console.WriteLine("renameFolder: " + sourcePath + " " + targetPath + " " + ex.Message);
        throw ex;
     }
  }

  private static void DeleteFileSystemInfo(FileSystemInfo fsi) {
     fsi.Attributes = FileAttributes.Normal;
     var di = fsi as DirectoryInfo;

     if (di != null)
     {
        foreach (var dirInfo in di.GetFileSystemInfos())
        {
           DeleteFileSystemInfo(dirInfo);
        }
     }

     fsi.Delete();
  }

Answer 11

NET 框架 3.5 和 NET 框架 4 及更高版本的解决方案：

#region DeleteWithReadOnly
internal static void DeleteWithReadOnly(this DirectoryInfo di)
{
   foreach (FileSystemInfo fsi in di.EnumerateFileSystemInfos("*", SearchOption.AllDirectories))
   {
      fsi.Attributes = FileAttributes.Normal;
   }
   di.Delete(true);
}
#endregion

#region DeleteWithReadOnlyNET3_5
internal static void DeleteWithReadOnlyNET3_5(this DirectoryInfo di)
{
   foreach (FileSystemInfo fsi in di.GetFiles("*", SearchOption.AllDirectories))
   {
      fsi.Attributes = FileAttributes.Normal;
   }
   di.Delete(true);
}
#endregion

用法：

DirectoryInfo di = new DirectoryInfo(@"C:\TMP");
di.DeleteWithReadOnly();