如何获取当前系统用户对文件/文件夹的操作权限？
1.获取安全信息DirectorySecurity
DirectorySecurity fileAcl = Directory.GetAccessControl(folder);
通过Directory.GetAccessControl获取文件夹的权限/安全信息
详细介绍，可参考MSDN官方文档
对文件/文件夹权限的详细操作，可参考一篇博客C#文件夹权限操作
2. 获取文件夹访问权限列表FileSystemAccessRule
var rules = fileAcl.GetAccessRules(true, true, typeof(System.Security.Principal.NTAccount)).OfType<FileSystemAccessRule>().ToList();
GetAccessRules()方法返回的是AuthorizationRule集合，此处只需要获取文件权限。
FileSystemAccessRule继承自AuthorizationRule，并新增俩个属性
- AccessControlType -- 枚举 Allow/Deny
- FileSystemRights -- 对文件的访问权限详细信息（读/写等），可见下面列表：
1 /// <summary>定义要创建访问和审核规则时使用的访问权限。</summary> 2 [Flags] 3 public enum FileSystemRights 4 { 5 ReadData = 1, 6 ListDirectory = ReadData, // 0x00000001 7 WriteData = 2, 8 CreateFiles = WriteData, // 0x00000002 9 AppendData = 4, 10 CreateDirectories = AppendData, // 0x00000004 11 ReadExtendedAttributes = 8, 12 WriteExtendedAttributes = 16, // 0x00000010 13 ExecuteFile = 32, // 0x00000020 14 Traverse = ExecuteFile, // 0x00000020 15 DeleteSubdirectoriesAndFiles = 64, // 0x00000040 16 ReadAttributes = 128, // 0x00000080 17 WriteAttributes = 256, // 0x00000100 18 Delete = 65536, // 0x00010000 19 ReadPermissions = 131072, // 0x00020000 20 ChangePermissions = 262144, // 0x00040000 21 TakeOwnership = 524288, // 0x00080000 22 Synchronize = 1048576, // 0x00100000 23 FullControl = Synchronize | TakeOwnership | ChangePermissions | ReadPermissions | Delete | WriteAttributes | ReadAttributes | DeleteSubdirectoriesAndFiles | Traverse | WriteExtendedAttributes | ReadExtendedAttributes | CreateDirectories | CreateFiles | ListDirectory, // 0x001F01FF 24 Read = ReadPermissions | ReadAttributes | ReadExtendedAttributes | ListDirectory, // 0x00020089 25 ReadAndExecute = Read | Traverse, // 0x000200A9 26 Write = WriteAttributes | WriteExtendedAttributes | CreateDirectories | CreateFiles, // 0x00000116 27 Modify = Write | ReadAndExecute | Delete, // 0x000301BF 28 }
因为AuthorizationRule中，IdentityReference对应权限的用户/用户组标识，格式为："MYDOMAIN\MyAccount"
所以，如通过当前系统用户名与IdentityReference匹配，即可获取FileSystemAccessRule权限。如何获取用户名，见下一段落
3. 获取当前系统用户名/用户组
通过 System.Environment.UserDomainName 和 System.Environment.UserName 取得当前用户名
对当前系统用户名/用户组的其它操作，可参考
因此，将Path.Combine(Environment.UserDomainName, Environment.UserName)与IdentityReference.Value比较，获取当前用户对文件夹的权限信息
详细实现如下：
1 /// <summary> 2 /// 检查当前用户是否拥有此文件夹的操作权限 3 /// </summary> 4 /// <param name="folder"></param> 5 /// <returns></returns> 6 public static bool HasOperationPermission(string folder) 7 { 8 var currentUserIdentity = Path.Combine(Environment.UserDomainName, Environment.UserName); 9 10 DirectorySecurity fileAcl = Directory.GetAccessControl(folder); 11 var userAccessRules = fileAcl.GetAccessRules(true, true, typeof(System.Security.Principal.NTAccount)).OfType<FileSystemAccessRule>().Where(i=>i.IdentityReference.Value==currentUserIdentity).ToList(); 12 13 return userAccessRules.Any(i => i.AccessControlType == AccessControlType.Deny); 14 }
获取文件夹是否有删除权限（仅删除空文件夹）：
1 /// <summary> 2 /// 检查当前用户是否拥有此文件夹的删除操作权限 3 /// </summary> 4 /// <param name="folder"></param> 5 /// <returns></returns> 6 public static bool HasDeleteOperationPermission(string folder) 7 { 8 var currentUserIdentity = Path.Combine(Environment.UserDomainName, Environment.UserName); 9 10 DirectorySecurity fileAcl = Directory.GetAccessControl(folder); 11 var userAccessRules = fileAcl.GetAccessRules(true, true, typeof(System.Security.Principal.NTAccount)).OfType<FileSystemAccessRule>().Where(i => i.IdentityReference.Value == currentUserIdentity).ToList(); 12 13 if (userAccessRules.Count > 0 && 14 userAccessRules.Any(i => (i.FileSystemRights & FileSystemRights.Delete) != 0 && i.AccessControlType == AccessControlType.Allow)) 15 { 16 17 return true; 18 } 19 return false; 20 }