Sending Email using VB.NET
This article will demonstrate how using the Email Factory for .NET SMTP component you can create and send emails using VB.NET. In addition to support for SMTP, Email Factory for .NET also includes components for POP3, IMAP, POP3SSL, IMAPSSL and MIME.
 
The source code for this article is available for download and for viewing.
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The Email Factory for .NET SMTP component provides methods for communicating with an SMTP server. The process for establishing an interactive session with an SMTP server using the Email Factory for .NET component is as follows:
- Creating a new Smtp instance with events
- Establishing a connection
- Creating an email message
- Defining addressing and other message properties
- Defining the message body
- Adding message attachments
- Sending an email message
- Releasing a connection
Each of these processes is described in the sections below.
Before creating a new Smtp instance, ensure that the Jscape.Email scope is defined in your Imports statements, and that the Jscape.Email.dll is referenced in your project. Refer to Getting Started in the Email Factory for .NET Help for more information about adding the Jscape.Email.dll reference to your projects.
The Smtp component may publish one or more events during the lifetime of an SMTP session. Any object that subscribes to events published by the Smtp component can receive and process the following events.
- The ConnectedEvent is fired by the Smtp instance once a connection to the SMTP server has been established.
- The DisconnectedEvent is fired by the Smtp instance once the connection to the SMTP server has been released.
- The CommandSentEvent is fired by the Smtp instance for each command sent to the SMTP server.
- The DataReceivedEvent is fired by the Smtp instance for each response received from the SMTP server.
After you have the Jscape.Email.dll reference added to your project, you can define an Smtp instance with events.
Dim WithEvents mySmtp As Smtp = Nothing
To create a new Smtp instance, provide the SMTP server hostname as an argument.
mySmtp = New Smtp("hostname")
Now you can create the event handler methods for the Smtp events.
Public Sub OnConnected(ByVal sender As Object, ByVal e As SmtpConnectedEventArgs) Handles mySmtp.ConnectedEvent
Console.WriteLine("Connected to {0}", e.Host)
End Sub
Public Sub OnDisconnected(ByVal sender As Object, ByVal e As SmtpDisconnectedEventArgs) Handles mySmtp.DisconnectedEvent
Console.WriteLine("Disconnected.")
End Sub
Public Sub OnDataReceived(ByVal sender As Object, ByVal e As SmtpDataReceivedEventArgs) Handles mySmtp.DataReceivedEvent
Console.WriteLine("Response: " + e.Response)
End Sub
Public Sub OnCommandSent(ByVal sender As Object, ByVal e As SmtpCommandSentEventArgs) Handles mySmtp.CommandSentEvent
Console.WriteLine("Command: " + e.Command)
End Sub
Once an Smtp instance has been created and the Smtp event handlers defined, you may establish a connection to the SMTP server by invoking the Connect() method.
mySmtp.Connect()
To create an email message, construct a new EmailMessage instance passing the To: address and From: address to the constructor. You may also assign the To and From properties on the EmailMessage instance if you are using the default US-ASCII character set encoding. See the following section for more information about specifying message properties. If you are using another character set encoding, use the SetTo and SetFrom methods. Refer to the Email Factory for .NET Help for more information.
Public message As EmailMessage = Nothing
' create instance with To and From addresses
message = New EmailMessage("ToAddress", "FromAddress")
In addition to passing the To and From addresses to the EmailMessage constructor, you can specify the properties on the message instance. The EmailMessage class also has properties and methods for adding carbon-copy, blind-carbon-copy, and reply-to recipients, and message subject and priority.
Note: The To and From addresses are required properties.
message = New EmailMessage
message.To = "ToAddress"
message.From = "FromAddress"
message.Cc = "CcAddress"
message.Bcc = "BccAddress"
message.ReplyTo = "ReplyToAddress"
message.Priority = "normal"
message.Subject = "This is a test subject"
You can set the message body to the contents of a file, a database query result, or a hand-coded message, as shown in the following example. Refer to the Email Factory for .NET Help for more information about defining the message body contents from a FileStream.
message.SetBody("This is a sample message")
You can add one or more attachments to an email message by invoking the AddAttachment() method passing an Attachment instance as an argument. The attachment instance can be constructed by passing a file path as an argument.
Note: Due to the way that the message body is copied when adding attachments it is important that attachments be added only after the body of the message has been defined. Changing the Body, Content-Type, or Content-Transfer-Encoding of the message after attachments have been added may result in undesired effects.
Public att As Attachment = Nothing
att = New Attachment("c:\home\report.doc")
message.AddAttachment(att)
To send a message through an established connection simply invoke the Send() method passing the message instance as an argument.
mySmtp.Send(message)
To release an established connection simply invoke the Disconnect() method as follows:
mySmtp.Disconnect()
The source code for this article is available for download and for viewing.
View example source code
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