C#设置文件权限的方法

在开发中，我们经常会使用IO操作，例如创建，删除文件等操作。在项目中这样的需求也较多，我们也会经常对这些操作进行编码，但是对文件的权限进行设置，这样的操作可能会手动操作，现在介绍一种采用代码动态对文件设置权限的操作。

在对文件进行权限设置在DOtNet中，会采用FileSystemAccessRule类进行文件的权限操作。

1.现在看一下FileSystemAccessRule的实现代码：

 public FileSystemAccessRule(
      IdentityReference identity,
      FileSystemRights fileSystemRights,
      AccessControlType type )
      : this(
        identity,
        AccessMaskFromRights( fileSystemRights, type ),
        false,
        InheritanceFlags.None,
        PropagationFlags.None,
        type )
    {
    }

    public FileSystemAccessRule(
      String identity,
      FileSystemRights fileSystemRights,
      AccessControlType type )
      : this(
        new NTAccount(identity),
        AccessMaskFromRights( fileSystemRights, type ),
        false,
        InheritanceFlags.None,
        PropagationFlags.None,
        type )
    {
    }

    //
    // Constructor for creating access rules for folder objects
    //

    public FileSystemAccessRule(
      IdentityReference identity,
      FileSystemRights fileSystemRights,
      InheritanceFlags inheritanceFlags,
      PropagationFlags propagationFlags,
      AccessControlType type )
      : this(
        identity,
        AccessMaskFromRights( fileSystemRights, type ),
        false,
        inheritanceFlags,
        propagationFlags,
        type )
    {
    }

    public FileSystemAccessRule(
      String identity,
      FileSystemRights fileSystemRights,
      InheritanceFlags inheritanceFlags,
      PropagationFlags propagationFlags,
      AccessControlType type )
      : this(
        new NTAccount(identity),
        AccessMaskFromRights( fileSystemRights, type ),
        false,
        inheritanceFlags,
        propagationFlags,
        type )
    {
    }
    internal FileSystemAccessRule(
      IdentityReference identity,
      int accessMask,
      bool isInherited,
      InheritanceFlags inheritanceFlags,
      PropagationFlags propagationFlags,
      AccessControlType type )
      : base(
        identity,
        accessMask,
        isInherited,
        inheritanceFlags,
        propagationFlags,
        type )
    {
    }

    #endregion

    #region Public properties

    public FileSystemRights FileSystemRights
    {
      get { return RightsFromAccessMask( base.AccessMask ); }
    }

    internal static int AccessMaskFromRights( FileSystemRights fileSystemRights, AccessControlType controlType )
    {
      if (fileSystemRights < (FileSystemRights) 0 || fileSystemRights > FileSystemRights.FullControl)
        throw new ArgumentOutOfRangeException("fileSystemRights", Environment.GetResourceString("Argument_InvalidEnumValue", fileSystemRights, "FileSystemRights"));
      Contract.EndContractBlock();

      if (controlType == AccessControlType.Allow) {
        fileSystemRights |= FileSystemRights.Synchronize;
      }
      else if (controlType == AccessControlType.Deny) {
        if (fileSystemRights != FileSystemRights.FullControl &&
          fileSystemRights != (FileSystemRights.FullControl & ~FileSystemRights.DeleteSubdirectoriesAndFiles))
          fileSystemRights &= ~FileSystemRights.Synchronize;
      }

      return ( int )fileSystemRights;
    }

    internal static FileSystemRights RightsFromAccessMask( int accessMask )
    {
      return ( FileSystemRights )accessMask;
    }

  }

2.由于FileSystemAccessRule继承自AccessRule，现在看一下AccessRule的源码：

/// <summary>
 /// 表示用户的标识、访问掩码和访问控制类型（允许或拒绝）的组合。<see cref="T:System.Security.AccessControl.AccessRule"/> 对象还包含有关子对象如何继承规则以及如何传播继承的信息。
 /// </summary>
 public abstract class AccessRule : AuthorizationRule
 {
  /// <summary>
  /// 使用指定的值初始化 <see cref="T:System.Security.AccessControl.AccessRule"/> 类的一个新实例。
  /// </summary>
  /// <param name="identity">应用访问规则的标识。此参数必须是可以强制转换为 <see cref="T:System.Security.Principal.SecurityIdentifier"/> 的对象。</param><param name="accessMask">此规则的访问掩码。访问掩码是一个 32 位的匿名位集合，其含义是由每个集成器定义的。</param><param name="isInherited">如果此规则继承自父容器，则为 true。</param><param name="inheritanceFlags">访问规则的继承属性。</param><param name="propagationFlags">继承的访问规则是否自动传播。如果 <paramref name="inheritanceFlags"/> 设置为 <see cref="F:System.Security.AccessControl.InheritanceFlags.None"/>，则将忽略传播标志。</param><param name="type">有效的访问控制类型。</param><exception cref="T:System.ArgumentException"><paramref name="identity"/> 参数的值不能强制转换为 <see cref="T:System.Security.Principal.SecurityIdentifier"/>，或者 <paramref name="type"/> 参数包含无效值。</exception><exception cref="T:System.ArgumentOutOfRangeException"><paramref name="accessMask"/> 参数的值为零，或者 <paramref name="inheritanceFlags"/> 或 <paramref name="propagationFlags"/> 参数包含无法识别的标志值。</exception>
  protected AccessRule(IdentityReference identity, int accessMask, bool isInherited, InheritanceFlags inheritanceFlags, PropagationFlags propagationFlags, AccessControlType type);
  /// <summary>
  /// 获取与此 <see cref="T:System.Security.AccessControl.AccessRule"/> 对象关联的 <see cref="T:System.Security.AccessControl.AccessControlType"/> 对象。
  /// </summary>
  ///
  /// <returns>
  /// 与此 <see cref="T:System.Security.AccessControl.AccessRule"/> 对象关联的 <see cref="T:System.Security.AccessControl.AccessControlType"/> 对象。
  /// </returns>
  public AccessControlType AccessControlType { get; }
 }

看来DotNet中实现文件权限设置的操作的类，现在提供几个具体的文件设置操作代码：

3.获取目录权限列表：

    /// <summary>
    /// 获取目录权限列表
    /// </summary>
    /// <param name="path">目录的路径。</param>
    /// <returns>指示目录的权限列表</returns>
    public IList<FileSystemRights> GetDirectoryPermission(string path)
    {
      try
      {
        if (!DirectoryExists(path))
          return null;

        IList<FileSystemRights> result = new List<FileSystemRights>();
        var dSecurity = Directory.GetAccessControl(new DirectoryInfo(path).FullName);
        foreach (FileSystemAccessRule rule in dSecurity.GetAccessRules(true, true, typeof(NTAccount)))
          result.Add(rule.FileSystemRights);

        return result;
      }
      catch (Exception e)
      {
        throw new Exception(e.Message, e);
      }
    }

4.设置目录权限

    /// <summary>
    ///设置目录权限
    /// </summary>
    /// <param name="path">目录的路径。</param>
    /// <param name="permission">在目录上设置的权限。</param>
    /// <returns>指示是否在目录上应用权限的值。</returns>
    public bool SetDirectoryPermission(string path, FileSystemRights permission)
    {
      try
      {
        if (!DirectoryExists(path))
          return false;

        var accessRule = new FileSystemAccessRule("Users", permission,
                      InheritanceFlags.None,
                      PropagationFlags.NoPropagateInherit,
                      AccessControlType.Allow);

        var info = new DirectoryInfo(path);
        var security = info.GetAccessControl(AccessControlSections.Access);

        bool result;
        security.ModifyAccessRule(AccessControlModification.Set, accessRule, out result);

        if (!result)
          return false;

        const InheritanceFlags iFlags = InheritanceFlags.ContainerInherit | InheritanceFlags.ObjectInherit;

        accessRule = new FileSystemAccessRule("Users", permission,
                      iFlags,
                      PropagationFlags.InheritOnly,
                      AccessControlType.Allow);

        security.ModifyAccessRule(AccessControlModification.Add, accessRule, out result);

        if (!result)
          return false;

        info.SetAccessControl(security);

        return true;
      }
      catch (Exception e)
      {
        throw new Exception(e.Message, e);
      }
    }

5.设置目录权限列表

  /// <summary>
  /// 设置目录权限列表
  /// </summary>
  /// <param name="path">目录的路径。</param>
  /// <param name="permissions">在目录上设置的权限。</param>
  /// <returns>指示是否在目录上应用权限的值。</returns>
  public bool SetDirectoryPermissions(string path, FileSystemRights[] permissions)
  {
   try
   {
    if (!DirectoryExists(path) || permissions == null || !permissions.Any())
     return false;

    foreach (var permission in permissions)
     if (!SetDirectoryPermission(path, permission))
      return false;

    return true;
   }
   catch (Exception e)
   {
    throw new Exception(e.Message, e);
   }
  }

以上就是C#设置文件权限的方法的详细内容，更多关于C#设置文件权限的资料请关注我们其它相关文章！