这是在c#中检查文件夹访问的一种非常有效的方法。它唯一可能失败的地方是，如果您需要在一个紧凑的循环中调用它，其中异常的开销可能是一个问题。

之前也有人问过类似的问题。

您的代码获得给定目录的DirectorySecurity，并正确处理异常(由于您无法访问安全性信息)。然而，在您的示例中，您实际上并没有询问返回的对象以查看允许哪些访问—我认为您需要添加这一点。

Here is a modified version of CsabaS's answer, which accounts for explicit deny access rules. The function goes through all FileSystemAccessRules for a directory, and checks if the current user is in a role which has access to a directory. If no such roles are found or the user is in a role with denied access, the function returns false. To check read rights, pass FileSystemRights.Read to the function; for write rights, pass FileSystemRights.Write. If you want to check an arbitrary user's rights and not the current one's, substitute the currentUser WindowsIdentity for the desired WindowsIdentity. I would also advise against relying on functions like this to determine if the user can safely use the directory. This answer perfectly explains why.

    public static bool UserHasDirectoryAccessRights(string path, FileSystemRights accessRights)
    {
        var isInRoleWithAccess = false;

        try
        {
            var di = new DirectoryInfo(path);
            var acl = di.GetAccessControl();
            var rules = acl.GetAccessRules(true, true, typeof(NTAccount));

            var currentUser = WindowsIdentity.GetCurrent();
            var principal = new WindowsPrincipal(currentUser);
            foreach (AuthorizationRule rule in rules)
            {
                var fsAccessRule = rule as FileSystemAccessRule;
                if (fsAccessRule == null)
                    continue;

                if ((fsAccessRule.FileSystemRights & accessRights) > 0)
                {
                    var ntAccount = rule.IdentityReference as NTAccount;
                    if (ntAccount == null)
                        continue;

                    if (principal.IsInRole(ntAccount.Value))
                    {
                        if (fsAccessRule.AccessControlType == AccessControlType.Deny)
                            return false;
                        isInRoleWithAccess = true;
                    }
                }
            }
        }
        catch (UnauthorizedAccessException)
        {
            return false;
        }
        return isInRoleWithAccess;
    }

我同意阿什的看法，应该没问题。或者，您也可以使用声明性CAS，如果它们没有访问权限，则实际上从一开始就阻止程序运行。

据我所知，我相信一些CAS特性在c# 4.0中可能不存在，不确定这是否是一个问题。

例如，对于所有用户(内置用户)，此方法工作良好-享受。

public static bool HasFolderWritePermission(string destDir)
{
   if(string.IsNullOrEmpty(destDir) || !Directory.Exists(destDir)) return false;
   try
   {
      DirectorySecurity security = Directory.GetAccessControl(destDir);
      SecurityIdentifier users = new SecurityIdentifier(WellKnownSidType.BuiltinUsersSid, null);
      foreach(AuthorizationRule rule in security.GetAccessRules(true, true, typeof(SecurityIdentifier)))
      {
          if(rule.IdentityReference == users)
          {
             FileSystemAccessRule rights = ((FileSystemAccessRule)rule);
             if(rights.AccessControlType == AccessControlType.Allow)
             {
                    if(rights.FileSystemRights == (rights.FileSystemRights | FileSystemRights.Modify)) return true;
             }
          }
       }
       return false;
    }
    catch
    {
        return false;
    }
}

这是在c#中检查文件夹访问的一种非常有效的方法。它唯一可能失败的地方是，如果您需要在一个紧凑的循环中调用它，其中异常的开销可能是一个问题。

之前也有人问过类似的问题。