C# 判断用户是否对路径拥有访问权限

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

对文件/文件夹权限的详细操作，可参考一篇博客

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。

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   }

View Code

 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     }