So - I need to facilitate emailing a map from a custom .NET ArcIMS site. (built on DotNetNuke - screen shot below)

 In .NET we conventiently have the System.Web.Mail namespace and objects to help out with this. It's almost trivial to use...

Dim Email As New MailMessage
Email.To = "address@something.com"
Email.From = "from@something.com"
Email.Subject = "Hello"
Email.Body = "This is the email."
SmtpMail.SmtpServer = "localhost"
SmtpMail.Send(Email)

The issue is how to attach a map. There is an Attachemet object, but it only supports attaching FILES. So you say - big deal - ArcIMS has created a .gif file, just send that. Well, that's cool if ArcIMS is on the same physical machine as the .NET app, or if you can map a drive to ArcIMS's output location, but what happens when that's not possible? i.e. you need to retreive the map from the output location, and then attach it. Ideally you do this by loading the image from the URL using a WebClient object (this is easiest, maybe not fastest)...

Dim webC As WebClient = New System.Net.WebClient
Dim OutputBitmap As Bitmap = New Bitmap(webC.OpenRead(http://myims/output/map2.gif))

Great. Now I can save the bitmap out to a file, and attach it. Which is what I've done for v1 of this tool. The downside is that you need to setup a directory that your ASP.NET application can write to, and can clean up. This is a lot of work for very little gain. Would'nt it be great if you could just create an attachment from a stream?

Well, apparently there are a bunch of commercial SMTP components which can do this, and while I'm not against them, I can't legitmize $200 per server for this little function - so I looked for some open source stuff. I found some classes that send messages via SMTP without using System.Web.Mail - they get all old skool and speak SMTP and use TCP sockets. So this is the first part. They're mostly C# (and I'm a VB.NET kinda guy), but I may go ahead and extend them to support adding attachments via streams. We'll see if I need this, but wanted to write it up anyhow...