C# Signature:
[DllImport("ntdll.dll", SetLastError=true)] static extern IntPtr NtQueryInformationFile(IntPtr fileHandle, ref IO_STATUS_BLOCK IoStatusBlock, IntPtr pInfoBlock, uint length, FILE_INFORMATION_CLASS fileInformation);
VB Signature:
Declare Function NtQueryInformationFile Lib "ntdll.dll" (ByVal fileHandle As IntPtr, ByRef IoStatusBlock As IO_STATUS_BLOCK, ByVal pInfoBlock As IntPtr, ByVal length As UInteger, ByVal fileInformation As FILE_INFORMATION_CLASS) As IntPtr
VB User-Defined Types:
Structure IO_STATUS_BLOCK
Dim status As UInteger
Dim information As ULong
End Structure
Enum FILE_INFORMATION_CLASS
FileDirectoryInformation = 1
FileFullDirectoryInformation
FileBothDirectoryInformation
FileBasicInformation
FileStandardInformation
FileInternalInformation
FileEaInformation
FileAccessInformation
FileNameInformation
FileRenameInformation
FileLinkInformation
FileNamesInformation
FileDispositionInformation
FilePositionInformation
FileFullEaInformation
FileModeInformation = 16
FileAlignmentInformation
FileAllInformation
FileAllocationInformation
FileEndOfFileInformation
FileAlternateNameInformation
FileStreamInformation
FilePipeInformation
FilePipeLocalInformation
FilePipeRemoteInformation
FileMailslotQueryInformation
FileMailslotSetInformation
FileCompressionInformation
FileObjectIdInformation
FileCompletionInformation
FileMoveClusterInformation
FileQuotaInformation
FileReparsePointInformation
FileNetworkOpenInformation
FileAttributeTagInformation
FileTrackingInformation
FileIdBothDirectoryInformation
FileIdFullDirectoryInformation
FileValidDataLengthInformation
FileShortNameInformation
FileHardLinkInformation = 46
End Enum
C# User-Defined Types:
struct IO_STATUS_BLOCK
{
uint status;
ulong information;
}
enum FILE_INFORMATION_CLASS
{
FileDirectoryInformation = 1, // 1
FileFullDirectoryInformation, // 2
FileBothDirectoryInformation, // 3
FileBasicInformation, // 4
FileStandardInformation, // 5
FileInternalInformation, // 6
FileEaInformation, // 7
FileAccessInformation, // 8
FileNameInformation, // 9
FileRenameInformation, // 10
FileLinkInformation, // 11
FileNamesInformation, // 12
FileDispositionInformation, // 13
FilePositionInformation, // 14
FileFullEaInformation, // 15
FileModeInformation = 16, // 16
FileAlignmentInformation, // 17
FileAllInformation, // 18
FileAllocationInformation, // 19
FileEndOfFileInformation, // 20
FileAlternateNameInformation, // 21
FileStreamInformation, // 22
FilePipeInformation, // 23
FilePipeLocalInformation, // 24
FilePipeRemoteInformation, // 25
FileMailslotQueryInformation, // 26
FileMailslotSetInformation, // 27
FileCompressionInformation, // 28
FileObjectIdInformation, // 29
FileCompletionInformation, // 30
FileMoveClusterInformation, // 31
FileQuotaInformation, // 32
FileReparsePointInformation, // 33
FileNetworkOpenInformation, // 34
FileAttributeTagInformation, // 35
FileTrackingInformation, // 36
FileIdBothDirectoryInformation, // 37
FileIdFullDirectoryInformation, // 38
FileValidDataLengthInformation, // 39
FileShortNameInformation, // 40
FileHardLinkInformation=46 // 46
}
Alternative Managed API:
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Notes:
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Sample Code:
// Copyright 
Alex Shvedov
// Feel free to use this sample code in any way you want.
using System;
using System.Runtime.InteropServices; // for DllImport and friends
using Microsoft.Win32.SafeHandles; // for SafeHandle
using System.Collections.Generic; // for ParseFileAttributes helper function (List<FileAttributes>
only
using System.IO; // for test main (FileStream) only
using System.Text; // for test main (Encoding) only
using System.Threading; // for test main (Thread.Sleep) only
using System.Diagnostics; // for test main (Trace.Write[Line]) only
public class Nt {
#region interops
struct IO_STATUS_BLOCK {
internal uint status;
internal ulong information;
}
enum FILE_INFORMATION_CLASS {
FileDirectoryInformation = 1, // 1
FileFullDirectoryInformation, // 2
FileBothDirectoryInformation, // 3
FileBasicInformation, // 4
FileStandardInformation, // 5
FileInternalInformation, // 6
FileEaInformation, // 7
FileAccessInformation, // 8
FileNameInformation, // 9
FileRenameInformation, // 10
FileLinkInformation, // 11
FileNamesInformation, // 12
FileDispositionInformation, // 13
FilePositionInformation, // 14
FileFullEaInformation, // 15
FileModeInformation = 16, // 16
FileAlignmentInformation, // 17
FileAllInformation, // 18
FileAllocationInformation, // 19
FileEndOfFileInformation, // 20
FileAlternateNameInformation, // 21
FileStreamInformation, // 22
FilePipeInformation, // 23
FilePipeLocalInformation, // 24
FilePipeRemoteInformation, // 25
FileMailslotQueryInformation, // 26
FileMailslotSetInformation, // 27
FileCompressionInformation, // 28
FileObjectIdInformation, // 29
FileCompletionInformation, // 30
FileMoveClusterInformation, // 31
FileQuotaInformation, // 32
FileReparsePointInformation, // 33
FileNetworkOpenInformation, // 34
FileAttributeTagInformation, // 35
FileTrackingInformation, // 36
FileIdBothDirectoryInformation, // 37
FileIdFullDirectoryInformation, // 38
FileValidDataLengthInformation, // 39
FileShortNameInformation, // 40
FileHardLinkInformation = 46 // 46
}
[StructLayout(LayoutKind.Explicit)]
struct FILE_BASIC_INFORMATION {
[FieldOffset(0)]
internal long CreationTime;
[FieldOffset(8)]
internal long LastAccessTime;
[FieldOffset(16)]
internal long LastWriteTime;
[FieldOffset(24)]
internal long ChangeTime;
[FieldOffset(32)]
internal ulong FileAttributes;
}
[DllImport("ntdll.dll", SetLastError = true)]
static extern IntPtr NtQueryInformationFile(SafeFileHandle fileHandle, ref IO_STATUS_BLOCK IoStatusBlock, IntPtr pInfoBlock, uint length, FILE_INFORMATION_CLASS fileInformation);
#endregion interops
#region converter of bit-wise file attributes into a list
public static List<FileAttributes> ParseFileAttributes(ulong fileAttributes) {
List<FileAttributes> listOfFileAttributesPresent = new List<FileAttributes>();
FileAttributes[] allPossibleValues = new FileAttributes[] { // per definition of FileAttributes
FileAttributes.ReadOnly,
FileAttributes.Hidden,
FileAttributes.System,
FileAttributes.Directory,
FileAttributes.Archive,
FileAttributes.Device,
FileAttributes.Normal,
FileAttributes.Temporary,
FileAttributes.SparseFile,
FileAttributes.ReparsePoint,
FileAttributes.Compressed,
FileAttributes.Offline,
FileAttributes.NotContentIndexed,
FileAttributes.Encrypted,
};
foreach(FileAttributes currentFileAttribute in allPossibleValues) {
if((fileAttributes & (ulong)currentFileAttribute) != 0) {
listOfFileAttributesPresent.Add(currentFileAttribute);
}
}
return listOfFileAttributesPresent;
}
#endregion converter of bit-wise file attributes into a list
#region change time available only thru NtQueryInformationFile and only on NTFS volume
public static bool GetFourFileTimes(string path2file,
out DateTime creationTime, out DateTime lastAccessTime, out DateTime lastWriteTime, out DateTime changeTime, out ulong fileAttributes, out string errMsg) {
bool brc = false;
creationTime = default(DateTime);
lastAccessTime = default(DateTime);
lastWriteTime = default(DateTime);
changeTime = default(DateTime);
errMsg = string.Empty;
fileAttributes = 0;
IntPtr p_fbi = IntPtr.Zero;
try {
FILE_BASIC_INFORMATION fbi = new FILE_BASIC_INFORMATION();
IO_STATUS_BLOCK iosb = new IO_STATUS_BLOCK();
using(FileStream fs = new FileStream(path2file, FileMode.Open, FileAccess.Read, FileShare.Read)) {
p_fbi = Marshal.AllocHGlobal(Marshal.SizeOf(fbi));
IntPtr iprc = NtQueryInformationFile(fs.SafeFileHandle, ref iosb, p_fbi, (uint)Marshal.SizeOf(fbi), FILE_INFORMATION_CLASS.FileBasicInformation);
brc = iprc == IntPtr.Zero && iosb.status == 0;
if(brc) {
brc = false;
fbi = (FILE_BASIC_INFORMATION)Marshal.PtrToStructure(p_fbi, typeof(FILE_BASIC_INFORMATION));
creationTime = DateTime.FromFileTime(fbi.CreationTime);
lastAccessTime = DateTime.FromFileTime(fbi.LastAccessTime);
lastWriteTime = DateTime.FromFileTime(fbi.LastWriteTime);
changeTime = DateTime.FromFileTime(fbi.ChangeTime);
fileAttributes = fbi.FileAttributes;
brc = true;
}
}
} catch(Exception ex) {
brc = false; // JIC
errMsg = ex.Message;
} finally {
if(p_fbi != IntPtr.Zero) { Marshal.FreeHGlobal(p_fbi); }
}
return brc;
}
#endregion change time available only thru NtQueryInformationFile and only on NTFS volume
#region test main
static void Main(string[] args) {
// create a test file:
string path2file = "test.fle";
string contents = "contents of test.fle";
Trace.WriteLine("path2file=" + path2file);
using(FileStream fs = File.Create(path2file)) {
fs.Write(Encoding.ASCII.GetBytes(contents), 0, Encoding.ASCII.GetBytes(contents).Length);
}
FileAttributes fileAttributesBefore = File.GetAttributes(path2file);
Trace.Write("fileAttributesBefore=");
foreach(FileAttributes fa1 in Nt.ParseFileAttributes((ulong)fileAttributesBefore)) {
Trace.Write(fa1.ToString() + " ");
}
Trace.WriteLine("");
// wait a little (1.5 sec) and modify test file attributes:
Thread.Sleep(1500);
File.SetAttributes(path2file, FileAttributes.Normal);
Trace.WriteLine("");
// run the test:
DateTime creationTime, lastAccessTime, lastWriteTime, changeTime;
ulong fileAttributesAfter;
string errMsg;
bool brc = false;
brc = Nt.GetFourFileTimes(path2file, out creationTime, out lastAccessTime, out lastWriteTime, out changeTime, out fileAttributesAfter, out errMsg);
// print results:
if(!brc) {
Trace.WriteLine("Error: " + errMsg);
} else {
Trace.Write("fileAttributesAfter=");
foreach(FileAttributes fa1 in Nt.ParseFileAttributes(fileAttributesAfter)) {
Trace.Write(fa1.ToString() + " ");
}
Trace.WriteLine("");
Trace.WriteLine("lastWriteTime= " + lastWriteTime.ToString("o"));
Trace.WriteLine("creationTime= " + creationTime.ToString("o"));
Trace.WriteLine("lastAccessTime=" + lastAccessTime.ToString("o"));
Trace.WriteLine("changeTime= " + changeTime.ToString("o"));
}
}
// sample printout:
//path2file=test.fle
//fileAttributesBefore=Archive
//fileAttributesAfter=Normal
//lastWriteTime= 2011-03-13T13:40:46.1003635-04:00
//creationTime= 2011-03-13T13:35:17.3413635-04:00
//lastAccessTime=2011-03-13T13:40:04.8263635-04:00
//changeTime= 2011-03-13T13:40:47.6083635-04:00
#endregion test main
}
For FILE_INFORMATION_CLASS, see: http://msdn.microsoft.com/en-us/library/cc232064.aspx
