c#如何操作NTFS权限?

using Microsoft.Win32.Security;
Here's a method to add a dir, and set NTFS permissions on it for a given user: 
private Boolean CreateDir(String strSitePath, String strUserName) {       Boolean bOk;       try {              Directory.CreateDirectory(strSitePath);              SecurityDescriptor secDesc = SecurityDescriptor.GetFileSecurity(strSitePath, SECURITY_INFORMATION.DACL_SECURITY_INFORMATION);              Dacl dacl = secDesc.Dacl;              Sid sidUser = new Sid (strUserName);               // allow: folder, subfolder and files              // modify              dacl.AddAce (new AceAccessAllowed (sidUser, AccessType.GENERIC_WRITE | AccessType.GENERIC_READ | AccessType.DELETE | AccessType.GENERIC_EXECUTE , AceFlags.OBJECT_INHERIT_ACE | AceFlags.CONTAINER_INHERIT_ACE));                            // deny: this folder              // write attribs              // write extended attribs              // delete              // change permissions              // take ownership              DirectoryAccessType DAType = DirectoryAccessType.FILE_WRITE_ATTRIBUTES | DirectoryAccessType.FILE_WRITE_EA | DirectoryAccessType.DELETE | DirectoryAccessType.WRITE_OWNER | DirectoryAccessType.WRITE_DAC;              AccessType AType = (AccessType)DAType;              dacl.AddAce (new AceAccessDenied (sidUser, AType));               secDesc.SetDacl(dacl);              secDesc.SetFileSecurity(strSitePath, SECURITY_INFORMATION.DACL_SECURITY_INFORMATION);              bOk = true;       } catch {              bOk = false;       }       return bOk;