AttachmentType Class

[SerializableAttribute] 
[XmlTypeAttribute(Namespace="http://schemas.microsoft.com/exchange/services/2006/types")] 
[DesignerCategoryAttribute("code")] 
[XmlIncludeAttribute(typeof(ItemAttachmentType))] 
[DebuggerStepThroughAttribute] 
[XmlIncludeAttribute(typeof(FileAttachmentType))] 
[GeneratedCodeAttribute("wsdl", "2.0.50727.3038")] 
public class AttachmentType

static void CreateAttachment(ExchangeServiceBinding esb)
{
    // Create item attachment.
    MessageType message = new MessageType();
    message.Subject = "Example subject";
    message.Importance = ImportanceChoicesType.Low;
    message.ImportanceSpecified = true;

    ItemAttachmentType itemAttach = new ItemAttachmentType();
    itemAttach.Name = "Message Attachment Example";
    itemAttach.Item = message;

    // Create file attachment.
    FileAttachmentType fileAttach = new FileAttachmentType();
    fileAttach.Name = "filename.txt";
    fileAttach.ContentType = "text/plain";

    byte[] content;
    using (FileStream fileStream = new FileStream("C:\\cas.txt",
        FileMode.Open, FileAccess.Read))
    {
        content = new byte[fileStream.Length];
        fileStream.Read(content, 0, content.Length);
    }

    fileAttach.Content = content;

    // Create the CreateAttachment request.
    CreateAttachmentTypereqCreateAttach = new CreateAttachmentType();

    // Identify the item that will have the attachments.
    ItemIdType item = new ItemIdType();
    item.Id = "AAAlAE1BQG1h";
    item.ChangeKey = "DwAAABYAAA"; 
    
    // Add the parent item to the request.
    reqCreateAttach.ParentItemId = item;

    // Add attachments to the request.
    reqCreateAttach.Attachments = new AttachmentType[2];
    reqCreateAttach.Attachments[0] = itemAttach;
    reqCreateAttach.Attachments[1] = fileAttach;

    try
    {
        CreateAttachmentResponseType resp = esb.CreateAttachment(reqCreateAttach);
        ArrayOfResponseMessagesType aorit = resp.ResponseMessages;
        ResponseMessageType[] rmta = aorit.Items;

        foreach (ResponseMessageType rmt in rmta)
        {
            if (rmt.ResponseClass == ResponseClassType.Success)
            {
                AttachmentInfoResponseMessageType airmt = rmt as AttachmentInfoResponseMessageType;
                foreach (AttachmentType atch in airmt.Attachments)
                {
                    if (atch is ItemAttachmentType)
                    {
                        Console.WriteLine("Created item attachment");
                    }
                    else if (atch is FileAttachmentType)
                    {
                        Console.WriteLine("Created file attachment");
                    }
                    else
                    {
                        throw new Exception("Unknown attachment");
                    }
                }
            }
        }
    }
    catch (Exception e)
    {
        Console.WriteLine(e.Message);
    }
}