At the end if the post i have pasted my version of the code from Matthews and Patricks book (basicly i translated the VB from the book to C# using a reflector). Some conversions were made, for example i use a class not a struct because of null handling.
You use it like this:
InfoPathAttachment attachment = new InfoPathAttachment();
try
{
//remove binary InfoPath header
attachment = InfoPathAttachment.DecodeAttachment(document.text);
}
catch (Exception e)
{
System.Diagnostics.Debug.WriteLine(e);
throw new Exception("UploadDocument: InfoPath attachment decoding error: " + e);
}
byte[] bytes = attachment.FileData;
string fileName = attachment.FileName.Substring(0, attachment.FileName.Length - 1);//remove terminating zero
Then its just a matter of calling your imaging or custom web service.
Remember when you recieve the infopath attachment filename, that it is has a terminating zero, so you need to remove the last char to make your web service call well-formed.
have fun!
//AndersR
P.S a shame your first name isnt Carl or something! C Sharp would be the coolest coding name ever :-D
using System;
using System.Text;
using System.Runtime.InteropServices;
using System.Security.Permissions;
namespace Creuna.InfoPath
{
public class InfoPathAttachment
{
// Fields
public byte[] FileData;
public string FileName;
/// <summary>
/// .NET representation of the InfoPath File Attachment Header
/// </summary>
[ StructLayout(LayoutKind.Sequential, Pack=1) ]
private class AttachmentStructure
{
public int Signature;
public int HeaderSize;
public int InfopathVersion;
public int Reserved;
public int Filesize;
public int FilenameCharLen;
}
/// <summary>
/// converts a byte array to an AttachmentStructure
/// </summary>
/// <param name="attachmentArray"></param>
/// <returns>AttachmentStructure</returns>
private static AttachmentStructure BytesToHeaderStructure( byte[] attachmentArray )
{
int structureLength = Marshal.SizeOf(typeof(InfoPathAttachment.AttachmentStructure));
if (attachmentArray.Length < structureLength)
return null;
//Allocates memory from the unmanaged memory
IntPtr pointer = Marshal.AllocHGlobal(structureLength);
//Copy data from a one-dimensional, managed 8-bit unsigned integer array to an unmanaged memory pointer
Marshal.Copy(attachmentArray, 0, pointer, structureLength);
//Marshal data from an unmanaged block of memory to a managed object
AttachmentStructure attachmentStructure = (AttachmentStructure) Marshal.PtrToStructure(pointer, typeof(AttachmentStructure));
Marshal.FreeHGlobal(pointer);
return attachmentStructure;
}
public static int Base64EncodedLength(int cb)
{
//The base64 encoded header will always be 4/3 the size of the
//binary version, rounded up to a multiple of 4.
return (int) Math.Round((double) (Math.Ceiling(((double) cb) / 3) * 4));
}
/// <summary>
///
/// </summary>
/// <param name="InnerTextAttachment"></param>
/// <returns></returns>
public static InfoPathAttachment DecodeAttachment(string InnerTextAttachment)
{
AttachmentStructure attachmentStructure = new AttachmentStructure();
InfoPathAttachment infoPathAttachment = new InfoPathAttachment();
//get encoded length of header
int cbHeaderEncoded = InfoPathAttachment.Base64EncodedLength(Marshal.SizeOf(attachmentStructure.GetType()));
if ( InnerTextAttachment.Length < cbHeaderEncoded )
{
throw new Exception("Encoded string is not long enough to include header.");
}
//decode header from string to byte
byte[] rgHeader = Convert.FromBase64String(InnerTextAttachment.Substring(0, cbHeaderEncoded));
//decode header from bytes to structure
attachmentStructure = InfoPathAttachment.BytesToHeaderStructure(rgHeader);
//check the signature
//1095125447 dec is 0x414649c7 hex, or {199, 73, 70, 65}.
if (!attachmentStructure.Signature.Equals(0x414649c7))
{
throw new Exception("Signature does not match InfoPath attachment signature.");
}
//Check the header size.
//The size of the header does not include the size of the signature.
int headerSizeRequired = Marshal.SizeOf(attachmentStructure.GetType()) - 4;
if (!attachmentStructure.HeaderSize.Equals(headerSizeRequired))
{
throw new Exception("Header size does not match expected size.");
}
//Check body
int cbBodyEncoded = InfoPathAttachment.Base64EncodedLength((attachmentStructure.FilenameCharLen * 2) + attachmentStructure.Filesize);
if (InnerTextAttachment.Length < (cbHeaderEncoded + cbBodyEncoded))
{
throw new Exception("Encoded string is not long enough to include body.");
}
byte[] rgBody = Convert.FromBase64String(InnerTextAttachment.Substring(cbHeaderEncoded, cbBodyEncoded));
//copy out filename
infoPathAttachment.FileName = Encoding.Unicode.GetString(rgBody, 0, attachmentStructure.FilenameCharLen * 2);
//copy out the rest of the file bytes
infoPathAttachment.FileData = (byte[]) Array.CreateInstance(typeof(byte), attachmentStructure.Filesize);
Array.Copy(rgBody, (int) (attachmentStructure.FilenameCharLen * 2), infoPathAttachment.FileData, 0, attachmentStructure.Filesize);
return infoPathAttachment;
}
}
}