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Fixed issue with exception attempting to access protected memory
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;
using System.Runtime.InteropServices.ComTypes;
using System.Reflection;
using System.IO;
using System.Windows;
namespace Helpers
{
/// <summary>
/// Provides a format-independant machanism for transfering data with support for outlook messages and attachments.
/// </summary>
public class OutlookDataObject : System.Windows.IDataObject
{
#region NativeMethods
private class NativeMethods
{
[DllImport("kernel32.dll")]
static extern IntPtr GlobalLock(IntPtr hMem);
[DllImport("ole32.dll", PreserveSig = false)]
public static extern ILockBytes CreateILockBytesOnHGlobal(IntPtr hGlobal, bool fDeleteOnRelease);
[DllImport("OLE32.DLL", CharSet = CharSet.Auto, PreserveSig = false)]
public static extern IntPtr GetHGlobalFromILockBytes(ILockBytes pLockBytes);
[DllImport("OLE32.DLL", CharSet = CharSet.Unicode, PreserveSig = false)]
public static extern IStorage StgCreateDocfileOnILockBytes(ILockBytes plkbyt, uint grfMode, uint reserved);
[ComImport, InterfaceType(ComInterfaceType.InterfaceIsIUnknown), Guid("0000000B-0000-0000-C000-000000000046")]
public interface IStorage
{
[return: MarshalAs(UnmanagedType.Interface)]
IStream CreateStream([In, MarshalAs(UnmanagedType.BStr)] string pwcsName, [In, MarshalAs(UnmanagedType.U4)] int grfMode, [In, MarshalAs(UnmanagedType.U4)] int reserved1, [In, MarshalAs(UnmanagedType.U4)] int reserved2);
[return: MarshalAs(UnmanagedType.Interface)]
IStream OpenStream([In, MarshalAs(UnmanagedType.BStr)] string pwcsName, IntPtr reserved1, [In, MarshalAs(UnmanagedType.U4)] int grfMode, [In, MarshalAs(UnmanagedType.U4)] int reserved2);
[return: MarshalAs(UnmanagedType.Interface)]
IStorage CreateStorage([In, MarshalAs(UnmanagedType.BStr)] string pwcsName, [In, MarshalAs(UnmanagedType.U4)] int grfMode, [In, MarshalAs(UnmanagedType.U4)] int reserved1, [In, MarshalAs(UnmanagedType.U4)] int reserved2);
[return: MarshalAs(UnmanagedType.Interface)]
IStorage OpenStorage([In, MarshalAs(UnmanagedType.BStr)] string pwcsName, IntPtr pstgPriority, [In, MarshalAs(UnmanagedType.U4)] int grfMode, IntPtr snbExclude, [In, MarshalAs(UnmanagedType.U4)] int reserved);
void CopyTo(int ciidExclude, [In, MarshalAs(UnmanagedType.LPArray)] Guid[] pIIDExclude, IntPtr snbExclude, [In, MarshalAs(UnmanagedType.Interface)] IStorage stgDest);
void MoveElementTo([In, MarshalAs(UnmanagedType.BStr)] string pwcsName, [In, MarshalAs(UnmanagedType.Interface)] IStorage stgDest, [In, MarshalAs(UnmanagedType.BStr)] string pwcsNewName, [In, MarshalAs(UnmanagedType.U4)] int grfFlags);
void Commit(int grfCommitFlags);
void Revert();
void EnumElements([In, MarshalAs(UnmanagedType.U4)] int reserved1, IntPtr reserved2, [In, MarshalAs(UnmanagedType.U4)] int reserved3, [MarshalAs(UnmanagedType.Interface)] out object ppVal);
void DestroyElement([In, MarshalAs(UnmanagedType.BStr)] string pwcsName);
void RenameElement([In, MarshalAs(UnmanagedType.BStr)] string pwcsOldName, [In, MarshalAs(UnmanagedType.BStr)] string pwcsNewName);
void SetElementTimes([In, MarshalAs(UnmanagedType.BStr)] string pwcsName, [In] System.Runtime.InteropServices.ComTypes.FILETIME pctime, [In] System.Runtime.InteropServices.ComTypes.FILETIME patime, [In] System.Runtime.InteropServices.ComTypes.FILETIME pmtime);
void SetClass([In] ref Guid clsid);
void SetStateBits(int grfStateBits, int grfMask);
void Stat([Out]out System.Runtime.InteropServices.ComTypes.STATSTG pStatStg, int grfStatFlag);
}
[ComImport, Guid("0000000A-0000-0000-C000-000000000046"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
public interface ILockBytes
{
void ReadAt([In, MarshalAs(UnmanagedType.U8)] long ulOffset, [Out, MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] byte[] pv, [In, MarshalAs(UnmanagedType.U4)] int cb, [Out, MarshalAs(UnmanagedType.LPArray)] int[] pcbRead);
void WriteAt([In, MarshalAs(UnmanagedType.U8)] long ulOffset, IntPtr pv, [In, MarshalAs(UnmanagedType.U4)] int cb, [Out, MarshalAs(UnmanagedType.LPArray)] int[] pcbWritten);
void Flush();
void SetSize([In, MarshalAs(UnmanagedType.U8)] long cb);
void LockRegion([In, MarshalAs(UnmanagedType.U8)] long libOffset, [In, MarshalAs(UnmanagedType.U8)] long cb, [In, MarshalAs(UnmanagedType.U4)] int dwLockType);
void UnlockRegion([In, MarshalAs(UnmanagedType.U8)] long libOffset, [In, MarshalAs(UnmanagedType.U8)] long cb, [In, MarshalAs(UnmanagedType.U4)] int dwLockType);
void Stat([Out]out System.Runtime.InteropServices.ComTypes.STATSTG pstatstg, [In, MarshalAs(UnmanagedType.U4)] int grfStatFlag);
}
[StructLayout(LayoutKind.Sequential)]
public sealed class POINTL
{
public int x;
public int y;
}
[StructLayout(LayoutKind.Sequential)]
public sealed class SIZEL
{
public int cx;
public int cy;
}
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
public sealed class FILEGROUPDESCRIPTORA
{
public uint cItems;
public FILEDESCRIPTORA fgd;
}
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
public sealed class FILEDESCRIPTORA
{
public uint dwFlags;
public Guid clsid;
public SIZEL sizel;
public POINTL pointl;
public uint dwFileAttributes;
public System.Runtime.InteropServices.ComTypes.FILETIME ftCreationTime;
public System.Runtime.InteropServices.ComTypes.FILETIME ftLastAccessTime;
public System.Runtime.InteropServices.ComTypes.FILETIME ftLastWriteTime;
public uint nFileSizeHigh;
public uint nFileSizeLow;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
public string cFileName;
}
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public sealed class FILEGROUPDESCRIPTORW
{
public uint cItems;
public FILEDESCRIPTORW fgd;
}
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public sealed class FILEDESCRIPTORW
{
public uint dwFlags;
public Guid clsid;
public SIZEL sizel;
public POINTL pointl;
public uint dwFileAttributes;
public System.Runtime.InteropServices.ComTypes.FILETIME ftCreationTime;
public System.Runtime.InteropServices.ComTypes.FILETIME ftLastAccessTime;
public System.Runtime.InteropServices.ComTypes.FILETIME ftLastWriteTime;
public uint nFileSizeHigh;
public uint nFileSizeLow;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
public string cFileName;
}
}
#endregion
#region Property(s)
/// <summary>
/// Holds the <see cref="System.Windows.IDataObject"/> that this class is wrapping
/// </summary>
private System.Windows.IDataObject underlyingDataObject;
/// <summary>
/// Holds the <see cref="System.Runtime.InteropServices.ComTypes.IDataObject"/> interface to the <see cref="System.Windows.IDataObject"/> that this class is wrapping.
/// </summary>
private System.Runtime.InteropServices.ComTypes.IDataObject comUnderlyingDataObject;
/// <summary>
/// Holds the internal ole <see cref="System.Windows.IDataObject"/> to the <see cref="System.Windows.IDataObject"/> that this class is wrapping.
/// </summary>
private System.Windows.IDataObject oleUnderlyingDataObject;
/// <summary>
/// Holds the <see cref="MethodInfo"/> of the "GetDataFromHGLOBAL" method of the internal ole <see cref="System.Windows.IDataObject"/>.
/// </summary>
private MethodInfo getDataFromHGLOBALMethod;
#endregion
#region Constructor(s)
/// <summary>
/// Initializes a new instance of the <see cref="OutlookDataObject"/> class.
/// </summary>
/// <param name="underlyingDataObject">The underlying data object to wrap.</param>
public OutlookDataObject(System.Windows.IDataObject underlyingDataObject)
{
//get the underlying dataobject and its ComType IDataObject interface to it
this.underlyingDataObject = underlyingDataObject;
this.comUnderlyingDataObject = (System.Runtime.InteropServices.ComTypes.IDataObject)this.underlyingDataObject;
//get the internal ole dataobject and its GetDataFromHGLOBAL so it can be called later
FieldInfo innerDataField = this.underlyingDataObject.GetType().GetField("_innerData", BindingFlags.NonPublic | BindingFlags.Instance);
this.oleUnderlyingDataObject = (System.Windows.IDataObject)innerDataField.GetValue(this.underlyingDataObject);
this.getDataFromHGLOBALMethod = this.oleUnderlyingDataObject.GetType().GetMethod("GetDataFromHGLOBAL", BindingFlags.NonPublic | BindingFlags.Instance);
}
#endregion
#region IDataObject Members
/// <summary>
/// Retrieves the data associated with the specified class type format.
/// </summary>
/// <param name="format">A <see cref="T:System.Type"></see> representing the format of the data to retrieve. See <see cref="T:System.Windows.DataFormats"></see> for predefined formats.</param>
/// <returns>
/// The data associated with the specified format, or null.
/// </returns>
public object GetData(Type format)
{
return this.GetData(format.FullName);
}
/// <summary>
/// Retrieves the data associated with the specified data format.
/// </summary>
/// <param name="format">The format of the data to retrieve. See <see cref="T:System.Windows.DataFormats"></see> for predefined formats.</param>
/// <returns>
/// The data associated with the specified format, or null.
/// </returns>
public object GetData(string format)
{
return this.GetData(format, true);
}
/// <summary>
/// Retrieves the data associated with the specified data format, using a Boolean to determine whether to convert the data to the format.
/// </summary>
/// <param name="format">The format of the data to retrieve. See <see cref="T:System.Windows.DataFormats"></see> for predefined formats.</param>
/// <param name="autoConvert">true to convert the data to the specified format; otherwise, false.</param>
/// <returns>
/// The data associated with the specified format, or null.
/// </returns>
public object GetData(string format, bool autoConvert)
{
//handle the "FileGroupDescriptor" and "FileContents" format request in this class otherwise pass through to underlying IDataObject
switch (format)
{
case "FileGroupDescriptor":
//override the default handling of FileGroupDescriptor which returns a
//MemoryStream and instead return a string array of file names
IntPtr fileGroupDescriptorAPointer = IntPtr.Zero;
try
{
//use the underlying IDataObject to get the FileGroupDescriptor as a MemoryStream
MemoryStream fileGroupDescriptorStream = (MemoryStream)this.underlyingDataObject.GetData("FileGroupDescriptor", autoConvert);
byte[] fileGroupDescriptorBytes = new byte[fileGroupDescriptorStream.Length];
fileGroupDescriptorStream.Read(fileGroupDescriptorBytes, 0, fileGroupDescriptorBytes.Length);
fileGroupDescriptorStream.Close();
//copy the file group descriptor into unmanaged memory
fileGroupDescriptorAPointer = Marshal.AllocHGlobal(fileGroupDescriptorBytes.Length);
Marshal.Copy(fileGroupDescriptorBytes, 0, fileGroupDescriptorAPointer, fileGroupDescriptorBytes.Length);
////marshal the unmanaged memory to to FILEGROUPDESCRIPTORA struct
//FIX FROM - https://stackoverflow.com/questions/27173844/accessviolationexception-after-copying-a-file-from-inside-a-zip-archive-to-the-c
int ITEMCOUNT = Marshal.ReadInt32(fileGroupDescriptorAPointer);
//create a new array to store file names in of the number of items in the file group descriptor
string[] fileNames = new string[ITEMCOUNT];
//get the pointer to the first file descriptor
IntPtr fileDescriptorPointer = (IntPtr)((long)fileGroupDescriptorAPointer + Marshal.SizeOf(ITEMCOUNT));
//loop for the number of files acording to the file group descriptor
for (int fileDescriptorIndex = 0; fileDescriptorIndex < ITEMCOUNT; fileDescriptorIndex++)
{
//marshal the pointer top the file descriptor as a FILEDESCRIPTORA struct and get the file name
NativeMethods.FILEDESCRIPTORA fileDescriptor = (NativeMethods.FILEDESCRIPTORA)Marshal.PtrToStructure(fileDescriptorPointer, typeof(NativeMethods.FILEDESCRIPTORA));
fileNames[fileDescriptorIndex] = fileDescriptor.cFileName;
//move the file descriptor pointer to the next file descriptor
fileDescriptorPointer = (IntPtr)((long)fileDescriptorPointer + Marshal.SizeOf(fileDescriptor));
}
//return the array of filenames
return fileNames;
}
finally
{
//free unmanaged memory pointer
Marshal.FreeHGlobal(fileGroupDescriptorAPointer);
}
case "FileGroupDescriptorW":
//override the default handling of FileGroupDescriptorW which returns a
//MemoryStream and instead return a string array of file names
IntPtr fileGroupDescriptorWPointer = IntPtr.Zero;
try
{
//use the underlying IDataObject to get the FileGroupDescriptorW as a MemoryStream
MemoryStream fileGroupDescriptorStream = (MemoryStream)this.underlyingDataObject.GetData("FileGroupDescriptorW");
byte[] fileGroupDescriptorBytes = new byte[fileGroupDescriptorStream.Length];
fileGroupDescriptorStream.Read(fileGroupDescriptorBytes, 0, fileGroupDescriptorBytes.Length);
fileGroupDescriptorStream.Close();
//copy the file group descriptor into unmanaged memory
fileGroupDescriptorWPointer = Marshal.AllocHGlobal(fileGroupDescriptorBytes.Length);
Marshal.Copy(fileGroupDescriptorBytes, 0, fileGroupDescriptorWPointer, fileGroupDescriptorBytes.Length);
//marshal the unmanaged memory to to FILEGROUPDESCRIPTORW struct
//FIX FROM - https://stackoverflow.com/questions/27173844/accessviolationexception-after-copying-a-file-from-inside-a-zip-archive-to-the-c
int ITEMCOUNT = Marshal.ReadInt32(fileGroupDescriptorWPointer);
//create a new array to store file names in of the number of items in the file group descriptor
string[] fileNames = new string[ITEMCOUNT];
//get the pointer to the first file descriptor
IntPtr fileDescriptorPointer = (IntPtr)((long)fileGroupDescriptorWPointer + Marshal.SizeOf(ITEMCOUNT));
//loop for the number of files acording to the file group descriptor
for (int fileDescriptorIndex = 0; fileDescriptorIndex < ITEMCOUNT; fileDescriptorIndex++)
{
//marshal the pointer top the file descriptor as a FILEDESCRIPTORW struct and get the file name
NativeMethods.FILEDESCRIPTORW fileDescriptor = (NativeMethods.FILEDESCRIPTORW)Marshal.PtrToStructure(fileDescriptorPointer, typeof(NativeMethods.FILEDESCRIPTORW));
fileNames[fileDescriptorIndex] = fileDescriptor.cFileName;
//move the file descriptor pointer to the next file descriptor
fileDescriptorPointer = (IntPtr)((long)fileDescriptorPointer + Marshal.SizeOf(fileDescriptor));
}
//return the array of filenames
return fileNames;
}
finally
{
//free unmanaged memory pointer
Marshal.FreeHGlobal(fileGroupDescriptorWPointer);
}
case "FileContents":
//override the default handling of FileContents which returns the
//contents of the first file as a memory stream and instead return
//a array of MemoryStreams containing the data to each file dropped
//
// FILECONTENTS requires a companion FILEGROUPDESCRIPTOR to be
// available so we bail out if we don't find one in the data object.
string fgdFormatName;
if (GetDataPresent("FileGroupDescriptorW"))
fgdFormatName = "FileGroupDescriptorW";
else if (GetDataPresent("FileGroupDescriptor"))
fgdFormatName = "FileGroupDescriptor";
else
return null;
//get the array of filenames which lets us know how many file contents exist
string[] fileContentNames = (string[])this.GetData(fgdFormatName);
//create a MemoryStream array to store the file contents
MemoryStream[] fileContents = new MemoryStream[fileContentNames.Length];
//loop for the number of files acording to the file names
for (int fileIndex = 0; fileIndex < fileContentNames.Length; fileIndex++)
{
//get the data at the file index and store in array
fileContents[fileIndex] = this.GetData(format, fileIndex);
}
//return array of MemoryStreams containing file contents
return fileContents;
}
//use underlying IDataObject to handle getting of data
return this.underlyingDataObject.GetData(format, autoConvert);
}
/// <summary>
/// Retrieves the data associated with the specified data format at the specified index.
/// </summary>
/// <param name="format">The format of the data to retrieve. See <see cref="T:System.Windows.DataFormats"></see> for predefined formats.</param>
/// <param name="index">The index of the data to retrieve.</param>
/// <returns>
/// A <see cref="MemoryStream"/> containing the raw data for the specified data format at the specified index.
/// </returns>
public MemoryStream GetData(string format, int index)
{
//create a FORMATETC struct to request the data with
FORMATETC formatetc = new FORMATETC();
formatetc.cfFormat = (short)DataFormats.GetDataFormat(format).Id;
formatetc.dwAspect = DVASPECT.DVASPECT_CONTENT;
formatetc.lindex = index;
formatetc.ptd = new IntPtr(0);
formatetc.tymed = TYMED.TYMED_ISTREAM | TYMED.TYMED_ISTORAGE | TYMED.TYMED_HGLOBAL;
//create STGMEDIUM to output request results into
STGMEDIUM medium = new STGMEDIUM();
//using the Com IDataObject interface get the data using the defined FORMATETC
this.comUnderlyingDataObject.GetData(ref formatetc, out medium);
//retrieve the data depending on the returned store type
switch (medium.tymed)
{
case TYMED.TYMED_ISTORAGE:
//to handle a IStorage it needs to be written into a second unmanaged
//memory mapped storage and then the data can be read from memory into
//a managed byte and returned as a MemoryStream
NativeMethods.IStorage iStorage = null;
NativeMethods.IStorage iStorage2 = null;
NativeMethods.ILockBytes iLockBytes = null;
System.Runtime.InteropServices.ComTypes.STATSTG iLockBytesStat;
try
{
//marshal the returned pointer to a IStorage object
iStorage = (NativeMethods.IStorage)Marshal.GetObjectForIUnknown(medium.unionmember);
Marshal.Release(medium.unionmember);
//create a ILockBytes (unmanaged byte array) and then create a IStorage using the byte array as a backing store
iLockBytes = NativeMethods.CreateILockBytesOnHGlobal(IntPtr.Zero, true);
iStorage2 = NativeMethods.StgCreateDocfileOnILockBytes(iLockBytes, 0x00001012, 0);
//copy the returned IStorage into the new IStorage
iStorage.CopyTo(0, null, IntPtr.Zero, iStorage2);
iLockBytes.Flush();
iStorage2.Commit(0);
//get the STATSTG of the ILockBytes to determine how many bytes were written to it
iLockBytesStat = new System.Runtime.InteropServices.ComTypes.STATSTG();
iLockBytes.Stat(out iLockBytesStat, 1);
int iLockBytesSize = (int)iLockBytesStat.cbSize;
//read the data from the ILockBytes (unmanaged byte array) into a managed byte array
byte[] iLockBytesContent = new byte[iLockBytesSize];
iLockBytes.ReadAt(0, iLockBytesContent, iLockBytesContent.Length, null);
//wrapped the managed byte array into a memory stream and return it
return new MemoryStream(iLockBytesContent);
}
finally
{
//release all unmanaged objects
Marshal.ReleaseComObject(iStorage2);
Marshal.ReleaseComObject(iLockBytes);
Marshal.ReleaseComObject(iStorage);
}
case TYMED.TYMED_ISTREAM:
//to handle a IStream it needs to be read into a managed byte and
//returned as a MemoryStream
IStream iStream = null;
System.Runtime.InteropServices.ComTypes.STATSTG iStreamStat;
try
{
//marshal the returned pointer to a IStream object
iStream = (IStream)Marshal.GetObjectForIUnknown(medium.unionmember);
Marshal.Release(medium.unionmember);
//get the STATSTG of the IStream to determine how many bytes are in it
iStreamStat = new System.Runtime.InteropServices.ComTypes.STATSTG();
iStream.Stat(out iStreamStat, 0);
int iStreamSize = (int)iStreamStat.cbSize;
//read the data from the IStream into a managed byte array
byte[] iStreamContent = new byte[iStreamSize];
iStream.Read(iStreamContent, iStreamContent.Length, IntPtr.Zero);
//wrapped the managed byte array into a memory stream and return it
return new MemoryStream(iStreamContent);
}
finally
{
//release all unmanaged objects
Marshal.ReleaseComObject(iStream);
}
case TYMED.TYMED_HGLOBAL:
//to handle a HGlobal the exisitng "GetDataFromHGLOBAL" method is invoked via
//reflection
return (MemoryStream)this.getDataFromHGLOBALMethod.Invoke(this.oleUnderlyingDataObject, new object[] { DataFormats.GetDataFormat((short)formatetc.cfFormat).Name, medium.unionmember });
}
return null;
}
/// <summary>
/// Determines whether data stored in this instance is associated with, or can be converted to, the specified format.
/// </summary>
/// <param name="format">A <see cref="T:System.Type"></see> representing the format for which to check. See <see cref="T:System.Windows.DataFormats"></see> for predefined formats.</param>
/// <returns>
/// true if data stored in this instance is associated with, or can be converted to, the specified format; otherwise, false.
/// </returns>
public bool GetDataPresent(Type format)
{
return this.underlyingDataObject.GetDataPresent(format);
}
/// <summary>
/// Determines whether data stored in this instance is associated with, or can be converted to, the specified format.
/// </summary>
/// <param name="format">The format for which to check. See <see cref="T:System.Windows.DataFormats"></see> for predefined formats.</param>
/// <returns>
/// true if data stored in this instance is associated with, or can be converted to, the specified format; otherwise false.
/// </returns>
public bool GetDataPresent(string format)
{
return this.underlyingDataObject.GetDataPresent(format);
}
/// <summary>
/// Determines whether data stored in this instance is associated with the specified format, using a Boolean value to determine whether to convert the data to the format.
/// </summary>
/// <param name="format">The format for which to check. See <see cref="T:System.Windows.DataFormats"></see> for predefined formats.</param>
/// <param name="autoConvert">true to determine whether data stored in this instance can be converted to the specified format; false to check whether the data is in the specified format.</param>
/// <returns>
/// true if the data is in, or can be converted to, the specified format; otherwise, false.
/// </returns>
public bool GetDataPresent(string format, bool autoConvert)
{
return this.underlyingDataObject.GetDataPresent(format, autoConvert);
}
/// <summary>
/// Returns a list of all formats that data stored in this instance is associated with or can be converted to.
/// </summary>
/// <returns>
/// An array of the names that represents a list of all formats that are supported by the data stored in this object.
/// </returns>
public string[] GetFormats()
{
return this.underlyingDataObject.GetFormats();
}
/// <summary>
/// Gets a list of all formats that data stored in this instance is associated with or can be converted to, using a Boolean value to determine whether to retrieve all formats that the data can be converted to or only native data formats.
/// </summary>
/// <param name="autoConvert">true to retrieve all formats that data stored in this instance is associated with or can be converted to; false to retrieve only native data formats.</param>
/// <returns>
/// An array of the names that represents a list of all formats that are supported by the data stored in this object.
/// </returns>
public string[] GetFormats(bool autoConvert)
{
return this.underlyingDataObject.GetFormats(autoConvert);
}
/// <summary>
/// Stores the specified data in this instance, using the class of the data for the format.
/// </summary>
/// <param name="data">The data to store.</param>
public void SetData(object data)
{
this.underlyingDataObject.SetData(data);
}
/// <summary>
/// Stores the specified data and its associated class type in this instance.
/// </summary>
/// <param name="format">A <see cref="T:System.Type"></see> representing the format associated with the data. See <see cref="T:System.Windows.DataFormats"></see> for predefined formats.</param>
/// <param name="data">The data to store.</param>
public void SetData(Type format, object data)
{
this.underlyingDataObject.SetData(format, data);
}
/// <summary>
/// Stores the specified data and its associated format in this instance.
/// </summary>
/// <param name="format">The format associated with the data. See <see cref="T:System.Windows.DataFormats"></see> for predefined formats.</param>
/// <param name="data">The data to store.</param>
public void SetData(string format, object data)
{
this.underlyingDataObject.SetData(format, data);
}
/// <summary>
/// Stores the specified data and its associated format in this instance, using a Boolean value to specify whether the data can be converted to another format.
/// </summary>
/// <param name="format">The format associated with the data. See <see cref="T:System.Windows.DataFormats"></see> for predefined formats.</param>
/// <param name="autoConvert">true to allow the data to be converted to another format; otherwise, false.</param>
/// <param name="data">The data to store.</param>
public void SetData(string format, object data, bool autoConvert)
{
this.underlyingDataObject.SetData(format, data, autoConvert);
}
#endregion
}
}
@JeannvanRooyen

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@JeannvanRooyen JeannvanRooyen commented May 26, 2015

Brilliant class. Worked 100% first time, no issues...

@uuf6429

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@uuf6429 uuf6429 commented Jun 25, 2015

This code doesn't compile since IDataObject doesn't exist in System.Windows namespace, but rather in System.Windows.Forms. Also, the non-public field _innerData is actually named innerData so GetField("_innerData", ... should actually be GetField("innerData", ....

EDIT by MattyBoy4444 - This was designed for WPF. There are other versions on the net for Window Forms.

@AndrewMiller1E

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@AndrewMiller1E AndrewMiller1E commented Nov 14, 2015

I believe there is a bug in the way that FILEGROUPDESCRIPTOR[A|W] classes are created in GetData. The call to Marshal.PtrToStructure will try to read 8 bytes out of the provided stream, but only the count of items (the first four bytes) is actually serialized. When processing a DataObject from Outlook there are no issues because the first FILEDESCRIPTOR[A|W] does not have any flags set, so Marshal.PtrToStructure just reads an extra four bytes with value 0. But for other DataObjects that's not necessarily true, and the call to Marshal.PtrToStructure may cause an exception attempting to access protected memory.

I fixed this issue by reading the count of items explicitly using BitConverter.ToUint32 and then manually creating the FILEGROUPDESCRIPTOR[A|W] class.

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@ghost ghost commented Nov 16, 2015

Thanks AndrewMiller1E for your comment. Indeed, I noticed that bug too. I'd like to better understand your solution please. What exactly did you change to fix the bug. Here is the current code as a reminder:

//marshal the unmanaged memory to to FILEGROUPDESCRIPTORA struct
var fileGroupDescriptorObject = Marshal.PtrToStructure(fileGroupDescriptorAPointer, typeof(NativeMethods.FILEGROUPDESCRIPTORA));
var fileGroupDescriptor = (NativeMethods.FILEGROUPDESCRIPTORA)fileGroupDescriptorObject;
(...)
//marshal the pointer top the file descriptor as a FILEDESCRIPTORA struct and get the file name
var fileDescriptor = (NativeMethods.FILEDESCRIPTORA)Marshal.PtrToStructure(fileDescriptorPointer, typeof(NativeMethods.FILEDESCRIPTORA));
fileNames[fileDescriptorIndex] = fileDescriptor.cFileName;

Thanks a lot in advance!

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@kickerskopp kickerskopp commented Nov 20, 2015

Works like a champ....
However I would also be interested in the fix Andrew suggested as I saw it crashing when for example dragging & dropping an attachment from the Google WebMail page...
From what I've seen in my tester they seem to use the same way to allow dragging to the desktop for example.

@MattyBoy4444

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@MattyBoy4444 MattyBoy4444 commented Dec 23, 2015

Thanks AndrewMiller1E !!!!

@junwei1994

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@junwei1994 junwei1994 commented Jul 30, 2020

Hi There,

I am from a software company. Our application is using the exactly same source code as above to allow users to drag and drop files or documents to our application, it even can allow to drag an attachment from Outlook to our application. It works fine.

But it comes to Outlook Version 2006 (Build 13001.20384 Click-to-Run), it failed to drag an attachment from Outlook to our application.

It fails at the line below:

Dim fileGroupDescriptorObject As Object = Marshal.PtrToStructure(fileGroupDescriptorWPointer, GetType(NativeMethods.FileGroupDescriptorw))

Then we modified our source code exactly same as line 282, it still fail anyway.

You may get the dummy application to debug via the link below:

https://drive.google.com/file/d/1PuhPa8RAWTwduzQMPG9EpF5Vidy-X9jH/view?usp=sharing

Just drag the attachment from an Outlook e-mail to the application and if successfully, it will prompt the messagebox with the file name of the attachment.

I would like to gather some ideas to figure out what's wrong. Thanks.

Best Regards,
Jun Wei

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