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Uploading an EML file to a Mailbox with Exchange Web Services

This is a handy little sample to have in your bag of tricks when you need to exchange messages between disparate messaging systems. This code sample is relatively straight forward in that it uses a file stream to read the byte stream of the EML file which is already in MIME format and then uses a createitem operation and posts the MIME content from the data stream to the Exchange Message Store. The only trick that comes in is when you create the Item in whatever folder you want you need to set the message flags property PR_Message_Flags so the message will appear as a normal Sent Mail in Outlook (otherwise it will just appear as a draft). Also you need to set the flag value so it will also appear as Read (unless you want to have it as unread.)

The sample itself uploads an eml file from the c: drive to a users sent items folder

I’ve put a download copy of the code here the code itself looks like

[warning this code sample may cause global warming if you don't configure your pc to shutdown when not in use thats what those power saving options are for in the control panel]

static void Main(string[] args)
{
String emFileName = @"c:\emchk1.eml";
FileStream fsFileStream = new FileStream(emFileName, FileMode.Open, FileAccess.Read);
byte[] bdBinaryData1 = ReadFully(fsFileStream,fsFileStream.Length);
ExchangeServiceBinding esb = new ExchangeServiceBinding();
esb.Credentials = new NetworkCredential("username", "password", "domain");
esb.Url = @"http://servername/EWS/exchange.asmx";
CreateItemType ciCreateItemRequest = new CreateItemType();
ciCreateItemRequest.MessageDisposition = MessageDispositionType.SaveOnly;
ciCreateItemRequest.MessageDispositionSpecified = true;
ciCreateItemRequest.SavedItemFolderId = new TargetFolderIdType();
DistinguishedFolderIdType sfSenditems = new DistinguishedFolderIdType();
sfSenditems.Id = DistinguishedFolderIdNameType.sentitems;
ciCreateItemRequest.SavedItemFolderId.Item = sfSenditems;
ciCreateItemRequest.Items = new NonEmptyArrayOfAllItemsType();
MessageType wsMessage = new MessageType();
MimeContentType mcMimeContnet = new MimeContentType();
mcMimeContnet.Value = Convert.ToBase64String(bdBinaryData1);
wsMessage.MimeContent = mcMimeContnet;
ExtendedPropertyType sfSentFlag = new ExtendedPropertyType();
PathToExtendedFieldType epExPath = new PathToExtendedFieldType();
epExPath.PropertyTag = "0x0E07";
epExPath.PropertyType = MapiPropertyTypeType.Integer;
sfSentFlag.ExtendedFieldURI = epExPath;
sfSentFlag.Item = "1";
wsMessage.IsRead = true;
wsMessage.ExtendedProperty = new ExtendedPropertyType[1];
wsMessage.ExtendedProperty[0] = sfSentFlag;
ciCreateItemRequest.Items.Items = new ItemType[1];
ciCreateItemRequest.Items.Items[0] = wsMessage;
CreateItemResponseType crCreateItemResponse = esb.CreateItem(ciCreateItemRequest);
if (crCreateItemResponse.ResponseMessages.Items[0].ResponseClass == ResponseClassType.Error)
{
throw new Exception(crCreateItemResponse.ResponseMessages.Items[0].MessageText);
}
else
{
}
}
public static byte[] ReadFully(Stream stream, long initialLength)
{
// ref Function from http://www.yoda.arachsys.com/csharp/readbinary.html
// If we've been passed an unhelpful initial length, just
// use 32K.
if (initialLength < initiallength =" 32768;" buffer =" new" read =" 0;" chunk =" stream.Read(buffer,"> 0)
{
read += chunk;

// If we've reached the end of our buffer, check to see if there's
// any more information
if (read == buffer.Length)
{
int nextByte = stream.ReadByte();

// End of stream? If so, we're done
if (nextByte == -1)
{
return buffer;
}

// Nope. Resize the buffer, put in the byte we've just
// read, and continue
byte[] newBuffer = new byte[buffer.Length * 2];
Array.Copy(buffer, newBuffer, buffer.Length);
newBuffer[read] = (byte)nextByte;
buffer = newBuffer;
read++;
}
}
// Buffer is now too big. Shrink it.
byte[] ret = new byte[read];
Array.Copy(buffer, ret, read);
return ret;
}
}
}

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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.