I'm trying to read the summary information of a NTFS file using .NET.
You know when you right click on a file and go to properties, you have
a bunch of tabs one of which is summary. I would like to be able to
write information there and be able to read it. I've done tons of
research and have found out how to do it using IPropertyStorage and
etc. I am able to write to that area of the file but cannot read. When
i try to read, i always get a blank even though the summary is full.
Here is my complete code, please help.

using System;
using System.Text;
using System.Runtime.InteropServices;
using System.IO;

namespace StructuredStorageWrapper
{
public enum SummaryPropId : int
{
Title = 0x00000002,
Subject = 0x00000003,
Author = 0x00000004,
Keywords = 0x00000005,
Comments = 0x00000006,
Template = 0x00000007,
LastSavedBy = 0x00000008,
RevisionNumber = 0x00000009,
TotalEditingTime = 0x0000000A,
LastPrinted = 0x0000000B,
CreateDateTime = 0x0000000C,
LastSaveDateTime = 0x0000000D,
NumPages = 0x0000000E,
NumWords = 0x0000000F,
NumChars = 0x00000010,
Thumbnail = 0x00000011,
AppName = 0x00000012,
Security = 0x00000013
}

public enum STGC : int
{
DEFAULT = 0,
OVERWRITE = 1,
ONLYIFCURRENT = 2,
DANGEROUSLYCOMMITMERELYTODISKCACHE = 4,
CONSOLIDATE = 8
}

public enum PROPSETFLAG : int
{
DEFAULT = 0,
NONSIMPLE = 1,
ANSI = 2,
UNBUFFERED = 4,
CASE_SENSITIVE = 8
}

public enum STGM : int
{
READ = 0x00000000,
WRITE = 0x00000001,
READWRITE = 0x00000002,
SHARE_DENY_NONE = 0x00000040,
SHARE_DENY_READ = 0x00000030,
SHARE_DENY_WRITE = 0x00000020,
SHARE_EXCLUSIVE = 0x00000010,
PRIORITY = 0x00040000,
CREATE = 0x00001000,
CONVERT = 0x00020000,
FAILIFTHERE = 0x00000000,
DIRECT = 0x00000000,
TRANSACTED = 0x00010000,
NOSCRATCH = 0x00100000,
NOSNAPSHOT = 0x00200000,
SIMPLE = 0x08000000,
DIRECT_SWMR = 0x00400000,
DELETEONRELEASE = 0x04000000
}

public enum STGFMT : int
{
STORAGE = 0,
FILE = 3,
ANY = 4,
DOCFILE = 5
}

[StructLayout(LayoutKind.Explicit, Size=8, CharSet=CharSet.Unicode)]
public struct PropSpec
{
[FieldOffset(0)] public int ulKind;
[FieldOffset(4)] public IntPtr Name_Or_ID;
}

[StructLayout(LayoutKind.Explicit, Size=16)]
public struct PropVariant
{
[FieldOffset(0)] public short variantType;
[FieldOffset(8)] public IntPtr pointerValue;
[FieldOffset(8)] public byte byteValue;
[FieldOffset(8)] public long longValue;

public void FromObject(object obj)
{
if (obj.GetType() == typeof(string))
{
this.variantType = (short)VarEnum.VT_LPWSTR;
this.pointerValue = Marshal.StringToHGlobalUni((string)obj);
}
}
}

[ComVisible(true), ComImport(),
Guid("0000013A-0000-0000-C000-000000000046"),
InterfaceType(ComInterfaceType.InterfaceIsIUnknown )]
public interface IPropertySetStorage
{
uint Create(
[In] ref System.Guid rfmtid,
[In] IntPtr pclsid,
[In] int grfFlags,
[In] int grfMode,
ref IPropertyStorage propertyStorage);

int Open(
[In] ref System.Guid rfmtid,
[In] int grfMode,
[Out] out IPropertyStorage propertyStorage);
}

[ComVisible(true), ComImport(),
Guid("00000138-0000-0000-C000-000000000046"),
InterfaceType(ComInterfaceType.InterfaceIsIUnknown )]
public interface IPropertyStorage
{
int ReadMultiple(
uint numProperties,
[MarshalAs(UnmanagedType.LPArray)] PropSpec[]
propertySpecifications,
[MarshalAs(UnmanagedType.LPArray)] PropVariant[] propertyValues);

int WriteMultiple(
uint numProperties,
[MarshalAs(UnmanagedType.Struct)] ref PropSpec
propertySpecification,
ref PropVariant propertyValues,
int propIDNameFirst);

uint Commit(
int commitFlags);
}

public enum HResults : uint
{
S_OK = 0,
STG_E_FILEALREADYEXISTS = 0x80030050
}

public class ole32
{
[StructLayout(LayoutKind.Explicit, Size=12,
CharSet=CharSet.Unicode)]
public struct STGOptions
{
[FieldOffset(0)] ushort usVersion;
[FieldOffset(2)] ushort reserved;
[FieldOffset(4)] uint uiSectorSize;
[FieldOffset(8), MarshalAs(UnmanagedType.LPWStr)] string
pwcsTemplateFile;
}

[DllImport("ole32.dll", CharSet=CharSet.Unicode)]
public static extern uint StgCreateStorageEx(
[MarshalAs(UnmanagedType.LPWStr)] string name,
int accessMode, int storageFileFormat, int fileBuffering,
IntPtr options, IntPtr reserved, ref System.Guid riid,
[MarshalAs(UnmanagedType.Interface)] ref IPropertySetStorage
propertySetStorage);

[DllImport("ole32.dll", CharSet=CharSet.Unicode)]
public static extern uint StgOpenStorageEx(
[MarshalAs(UnmanagedType.LPWStr)] string name,
int accessMode, int storageFileFormat, int fileBuffering,
IntPtr options, IntPtr reserved, ref System.Guid riid,
[MarshalAs(UnmanagedType.Interface)] ref IPropertySetStorage
propertySetStorage);
}

public class FileSummary
{
private FileInfo m_fileInfo;
public FileSummary(FileInfo fileInfo)
{
m_fileInfo = fileInfo;
//m_fileInfo.Open(FileMode.Open,FileAccess.ReadWrite ,FileShare.ReadWrite);

}

public void SetProperty(SummaryPropId summaryPropertID,string value)
{
// Open the file and its property set stream
IPropertySetStorage propSetStorage = null;
Guid IID_PropertySetStorage = new
Guid("0000013A-0000-0000-C000-000000000046");

uint hresult = ole32.StgOpenStorageEx(m_fileInfo.FullName,
(int)(STGM.SHARE_EXCLUSIVE | STGM.READWRITE),
(int)STGFMT.FILE,
0,
(IntPtr)0,
(IntPtr)0,
ref IID_PropertySetStorage,
ref propSetStorage);

// Open the Summary Information property set
Guid fmtid_SummaryProperties = new
Guid("F29F85E0-4FF9-1068-AB91-08002B27B3D9");
IPropertyStorage propStorage = null;

int hresult2 = propSetStorage.Open(
ref fmtid_SummaryProperties,
(int)(STGM.SIMPLE | STGM.READWRITE | STGM.SHARE_EXCLUSIVE),
out propStorage);

// Assemble a property descriptor for the specified property
PropSpec propertySpecification = new PropSpec();
propertySpecification.ulKind = 1;
propertySpecification.Name_Or_ID = new
IntPtr((int)summaryPropertID);

//Set the value wanted in a property variant
PropVariant propertyValue = new PropVariant();
propertyValue.FromObject(value);

// Pass the property spec and its new value to the WriteMultiple
method
propStorage.WriteMultiple(1, ref propertySpecification, ref
propertyValue, 0);

// Commit Changes
hresult = propStorage.Commit((int)STGC.DEFAULT);

// Release the Com objects
Marshal.ReleaseComObject(propStorage);
Marshal.ReleaseComObject(propSetStorage);
propStorage = null;
propSetStorage = null;

}

public string GetProperty(SummaryPropId summaryPropertID)
{
// Open the file and its property set stream
IPropertySetStorage propSetStorage = null;
Guid IID_PropertySetStorage = new
Guid("0000013A-0000-0000-C000-000000000046");

uint hresult = ole32.StgOpenStorageEx(m_fileInfo.FullName,
(int)(STGM.DIRECT_SWMR | STGM.READ | STGM.SHARE_DENY_NONE),
(int)STGFMT.FILE,
0,
System.IntPtr.Zero,
System.IntPtr.Zero,
ref IID_PropertySetStorage,
ref propSetStorage);

// Open the Summary Information property set
Guid fmtid_SummaryProperties = new
Guid("F29F85E0-4FF9-1068-AB91-08002B27B3D9");
IPropertyStorage propStorage = null;


int hresult2 = propSetStorage.Open(
ref fmtid_SummaryProperties,
(int)(STGM.DIRECT | STGM.SHARE_EXCLUSIVE),
out propStorage);

// Specify the property to be retrieved
PropSpec[] propSpecs = new PropSpec[1];
propSpecs[0].ulKind = 1;
propSpecs[0].Name_Or_ID = new IntPtr((int)summaryPropertID);
PropVariant[] propertyValues = new PropVariant[1];

// Retrieve the value
hresult2 = propStorage.ReadMultiple(1, propSpecs, propertyValues);

// Release the Com objects
Marshal.ReleaseComObject(propStorage);
Marshal.ReleaseComObject(propSetStorage);
propStorage = null;
propSetStorage = null;

return Marshal.PtrToStringUni(propertyValues[0].pointerValue);

}

}
}

// This should go in your startup class
static void Main()
{
FileSummary summary = new FileSummary(new
System.IO.FileInfo(@"c:\log.txt"));
summary.SetProperty(SummaryPropId.Title,"I can do whatever i want
here");
// That works
MessageBox.Show(summary.GetProperty(SummaryPropId. Title));
//This gives me blank
}

Thanks in advance

Mark

Can anyone help? Anyone? Maybe direct me to someone who can?

Mark

Hi Mark,

I suggest to you to download this Microsoft file: dsoFile.dll

Look at: http://support.microsoft.com/?id=224351