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Sending Attachments via the Exchange Web Services in Exchange 2007

Anyone who has every tried to send an attachment using WebDAV will know that it is a real pain compared with CDOSYS/CDOEX where it was generally just one line of code. The new Exchange Web Services fall somewhere in the middle of these two while not a simple 1 line of code the functionality is there it is just not immediately easy to work out how to do it. Here are two methods I’ve found that work if you want to send a message with an attachment (or just create an item or attach something to an already existing item). Note there are probably some other methods you can use but hopefully this is a little more helpful then just the XML in the current SDK. The first method is to create an item in a folder (eg the drafts folder) using a createitem operation then using the itemid and changeid returned from the create item request use the createattachment operation to attach the file to the new item you created. Then using the new changeid returned after the createattachment operation use a senditem operation to send the Message. The other method is to use a Createitem operation and set the MessageDisposition to SendAndSaveCopy which means the item that is created in this operation will also be sent at the same time. When using this method if you want to send a message with an attachment you need to post a MIME encoded copy of the message you want to send (with the attachment included). To MIME encode a message and its attachments you need to use a MIME Encoder/Parser. While in .NET 2.0 there is the Systen.NET.Mail and MIME classes these namespaces don’t give you direct access to the MIME stream of a message (you can post the message to a local directory and then reopen the file from the file system but this isn’t a very practial method). Fortunalty the good old CDOSYS/CDOEX still makes the best tried and tested MIME parser around and is more the adequate for the task.

I’ve created a couple of C# samples of both methods that use the Webservices proxy object and also a sample for Powershell and VBS that use CDOSYS to get a Base64 encoded version of the MIME Encoded message and then post this XML.

I’ve put a downloadable copy of all the samples here the create,attach send C# sample looks like

using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.IO;
using System.Xml.Serialization;
using ewsCreateAttachSend.mgne12v2;

namespace ewsCreateAttachSend
{
class Program
{
static void Main(string[] args)
{
Program coControlobject = new Program();
ExchangeServiceBinding ewsServiceBinding = new ExchangeServiceBinding();
ewsServiceBinding.Credentials = new NetworkCredential("username", "password", "domain");
ewsServiceBinding.Url = @"https://servername/EWS/exchange.asmx";
MessageType emMessage = new MessageType();
emMessage.Subject = "Test Attachment Send";
emMessage.Body = new BodyType();
emMessage.Body.BodyType1 = BodyTypeType.Text;
emMessage.Body.Value = "Blah,Blah";
emMessage.ItemClass = "IPM.Note";
emMessage.ToRecipients = new EmailAddressType[1];
emMessage.ToRecipients[0] = new EmailAddressType();
emMessage.ToRecipients[0].EmailAddress = "recipient@domain.com";
emMessage.Sensitivity = SensitivityChoicesType.Normal;
ItemIdType iiCreateItemid = coControlobject.CreateDraftMessage(ewsServiceBinding, emMessage);
iiCreateItemid = coControlobject.CreateAttachment(ewsServiceBinding, "c:\\file.ext", iiCreateItemid);
coControlobject.SendMessage(ewsServiceBinding,iiCreateItemid);
}
private ItemIdType CreateDraftMessage(ExchangeServiceBinding ewsServiceBinding,MessageType emMessage) {
ItemIdType iiItemid = new ItemIdType();
CreateItemType ciCreateItemRequest = new CreateItemType();
ciCreateItemRequest.MessageDisposition = MessageDispositionType.SaveOnly;
ciCreateItemRequest.MessageDispositionSpecified = true;
ciCreateItemRequest.SavedItemFolderId = new TargetFolderIdType();
DistinguishedFolderIdType dfDraftsFolder = new DistinguishedFolderIdType();
dfDraftsFolder.Id = DistinguishedFolderIdNameType.drafts;
ciCreateItemRequest.SavedItemFolderId.Item = dfDraftsFolder;
ciCreateItemRequest.Items = new NonEmptyArrayOfAllItemsType();
ciCreateItemRequest.Items.Items = new ItemType[1];
ciCreateItemRequest.Items.Items[0] = emMessage ;
CreateItemResponseType createItemResponse = ewsServiceBinding.CreateItem(ciCreateItemRequest);
if (createItemResponse.ResponseMessages.Items[0].ResponseClass == ResponseClassType.Error)
{
Console.WriteLine("Error Occured");
Console.WriteLine(createItemResponse.ResponseMessages.Items[0].MessageText);
}
else
{
ItemInfoResponseMessageType rmResponseMessage = createItemResponse.ResponseMessages.Items[0] as ItemInfoResponseMessageType;
Console.WriteLine("Item was created");
Console.WriteLine("Item ID : " + rmResponseMessage.Items.Items[0].ItemId.Id.ToString());
Console.WriteLine("ChangeKey : " + rmResponseMessage.Items.Items[0].ItemId.ChangeKey.ToString());
iiItemid.Id = rmResponseMessage.Items.Items[0].ItemId.Id.ToString();
iiItemid.ChangeKey = rmResponseMessage.Items.Items[0].ItemId.ChangeKey.ToString();
}

return iiItemid;
}
private ItemIdType CreateAttachment(ExchangeServiceBinding ewsServiceBinding,String fnFileName,ItemIdType iiCreateItemid) {
ItemIdType iiAttachmentItemid = new ItemIdType();
FileStream fsFileStream = new FileStream(fnFileName, System.IO.FileMode.Open, System.IO.FileAccess.Read);
byte[] bdBinaryData = new byte[fsFileStream.Length];
long brBytesRead = fsFileStream.Read(bdBinaryData, 0, (int)fsFileStream.Length);
fsFileStream.Close();
FileAttachmentType faFileAttach = new FileAttachmentType();
faFileAttach.Content = bdBinaryData;
faFileAttach.Name = fnFileName;
CreateAttachmentType amAttachmentMessage = new CreateAttachmentType();
amAttachmentMessage.Attachments = new AttachmentType[1];
amAttachmentMessage.Attachments[0] = faFileAttach;
amAttachmentMessage.ParentItemId = iiCreateItemid;
CreateAttachmentResponseType caCreateAttachmentResponse = ewsServiceBinding.CreateAttachment(amAttachmentMessage);
if (caCreateAttachmentResponse.ResponseMessages.Items[0].ResponseClass == ResponseClassType.Error)
{
Console.WriteLine("Error Occured");
Console.WriteLine(caCreateAttachmentResponse.ResponseMessages.Items[0].MessageText);
}
else {
AttachmentInfoResponseMessageType amAttachmentResponseMessage = caCreateAttachmentResponse.ResponseMessages.Items[0] as AttachmentInfoResponseMessageType;
Console.WriteLine("Attachment was created");
Console.WriteLine("Change Key : " + amAttachmentResponseMessage.Attachments[0].AttachmentId.RootItemChangeKey.ToString());
iiAttachmentItemid.Id = amAttachmentResponseMessage.Attachments[0].AttachmentId.RootItemId.ToString();
iiAttachmentItemid.ChangeKey = amAttachmentResponseMessage.Attachments[0].AttachmentId.RootItemChangeKey.ToString();
}
return iiAttachmentItemid;
}
private void SendMessage(ExchangeServiceBinding ewsServiceBinding,ItemIdType iiCreateItemid) {
SendItemType siSendItem = new SendItemType();
siSendItem.ItemIds = new BaseItemIdType[1];
siSendItem.SavedItemFolderId = new TargetFolderIdType();
DistinguishedFolderIdType siSentItemsFolder = new DistinguishedFolderIdType();
siSentItemsFolder.Id = DistinguishedFolderIdNameType.sentitems;
siSendItem.SavedItemFolderId.Item = siSentItemsFolder;
siSendItem.SaveItemToFolder = true; ;
siSendItem.ItemIds[0] = (BaseItemIdType)iiCreateItemid;
SendItemResponseType srSendItemReponseMessage = ewsServiceBinding.SendItem(siSendItem);
if (srSendItemReponseMessage.ResponseMessages.Items[0].ResponseClass == ResponseClassType.Error)
{
Console.WriteLine("Error Occured");
Console.WriteLine(srSendItemReponseMessage.ResponseMessages.Items[0].MessageText);
}
else {
Console.WriteLine("Message Sent");
}

}
}
}

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All sample scripts and source code is provided by for illustrative purposes only. All examples are untested in different environments and therefore, I cannot guarantee or imply reliability, serviceability, or function of these programs.

All code contained herein is provided to you "AS IS" without any warranties of any kind. The implied warranties of non-infringement, merchantability and fitness for a particular purpose are expressly disclaimed.