如果有人搜索解决方案:

If someone search the solution :

        DirectorySecurity directorySecurity = Directory.GetAccessControl(path);
        directorySecurity.SetAccessRuleProtection(true, keepPermissions);
        Directory.SetAccessControl(path, directorySecurity);

with keepPermissions为true，如果您想保留继承的权限.

with keepPermissions true if you want to keep inherited permissions.