Sending With Attachments

MIME attachments are represented by MimeAttachmentStream objects, and are managed by use of the Message.Attachments property, a collection of MimeAttachmentStreams. Due to the stream-based approach of PowerTCP Mail for .NET, adding attachments is very flexible. The source of attachments can be a file, a MemoryStream, or any other type of .NET Framework Stream. As a result, the ways an attachment can be created is limitless. This topic demonstrates three ways of creating an attachment.

To send an email with attachments, use the following steps.

Add the Smtp component to a new form.
Import the namespace of the component you would like to use using "Using" (C#) or "Imports" (VB.NET). Place the following code at the top of your file. Also, import System.IO as a FileStream will be used in this example.
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using Dart.PowerTCP.Mail; using System.IO;
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Imports Dart.PowerTCP.Mail Imports System.IO
Add a button to the form.

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using Dart.PowerTCP.Mail; using System.IO;

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Imports Dart.PowerTCP.Mail Imports System.IO

Email messages are represented by MessageStream objects. Create a MessageStream object. Place the following code in the Click event of the button added to the form in step 3.

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// Create a MessageStream MessageStream msg = new MessageStream(); // Set "To", "From", and "Subject" msg.To.Add(new MailAddress("you@yourserver.com")); msg.From = new MailAddress("me@myserver.com"); msg.Subject = "Test Message"; // Set the message text msg.Text = "This is a test message";

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// Create a MessageStream
MessageStream msg = new MessageStream();

// Set "To", "From", and "Subject"
msg.To.Add(new MailAddress("you@yourserver.com"));
msg.From = new MailAddress("me@myserver.com");
msg.Subject = "Test Message";

// Set the message text
msg.Text = "This is a test message";

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' Create a MessageStream Dim msg As New MessageStream() ' Set "To", "From", and "Subject" msg.To.Add(New MailAddress("you@yourserver.com")) msg.From = New MailAddress("me@myserver.com") msg.Subject = "Test Message" ' Set the message text msg.Text = "This is a test message"

Visual Basic

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' Create a MessageStream
Dim msg As New MessageStream()

' Set "To", "From", and "Subject"
msg.To.Add(New MailAddress("you@yourserver.com"))
msg.From = New MailAddress("me@myserver.com")
msg.Subject = "Test Message"

' Set the message text
msg.Text = "This is a test message"

In this example, three different attachments will be added, demonstrating three different techniques. First, create a MimeAttachmentStream object to use to encapsulate the attachments.

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MimeAttachmentStream attach = null;

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Dim attach As MimeAttachmentStream = Nothing

The first technique demonstrated passes a string filename into the MimeAttachmentStream constructor to create the attachment.

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// Method 1. Add an attachment using the filename attach = new MimeAttachmentStream("C:\\test\\file1.txt"); // Add it to the message. msg.Attachments.Add(attach); attach = null;

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' Method 1. Add an attachment using the filename attach = New MimeAttachmentStream("C:\test\file1.txt") ' Add it to the message. msg.Attachments.Add(attach) attach = Nothing

The second technique demonstrated passes a FileStream into the MimeAttachmentStream constructor to create the attachment.

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// Method 2. Add an attachment using a FileStream attach = new MimeAttachmentStream(new FileStream("C:\\test\\file2.txt", FileMode.Open)); // Add it to the message. msg.Attachments.Add(attach); attach = null;

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// Method 2. Add an attachment using a FileStream
attach = new MimeAttachmentStream(new FileStream("C:\\test\\file2.txt", FileMode.Open));

// Add it to the message.
msg.Attachments.Add(attach);
attach = null;

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' Method 2. Add an attachment using a FileStream attach = New MimeAttachmentStream(New FileStream("C:\test\file2.txt", FileMode.Open)) ' Add it to the message. msg.Attachments.Add(attach) attach = Nothing

Visual Basic

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' Method 2. Add an attachment using a FileStream
attach = New MimeAttachmentStream(New FileStream("C:\test\file2.txt", FileMode.Open))

' Add it to the message.
msg.Attachments.Add(attach)
attach = Nothing

The third technique demonstrated passes a MemoryStream into the MimeAttachmentStream constructor to create the attachment.

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// Method 3. Add an attachment from data in memory. string s = "This is a new attachment"; byte[] content = System.Text.Encoding.Default.GetBytes(s); MemoryStream m = new MemoryStream(content); attach = new MimeAttachmentStream(m, "file3.txt", TextPlain, QuotedPrintable, ""); // Add it to the message. msg.Attachments.Add(attach); attach = null;

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// Method 3. Add an attachment from data in memory.
string s = "This is a new attachment";
byte[] content = System.Text.Encoding.Default.GetBytes(s);
MemoryStream m = new MemoryStream(content);
attach = new MimeAttachmentStream(m, "file3.txt", TextPlain, QuotedPrintable, "");
                        
// Add it to the message.
msg.Attachments.Add(attach);
attach = null;

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' Method 3. Add an attachment from data in memory. Dim s As String = "This is a new attachment" Dim content As Byte() = System.Text.Encoding.Default.GetBytes(s) Dim m As New MemoryStream(content) attach = New MimeAttachmentStream(m, "file3.txt", TextPlain, QuotedPrintable, "") ' Add it to the message. msg.Attachments.Add(attach) attach = Nothing

Visual Basic

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' Method 3. Add an attachment from data in memory.
Dim s As String = "This is a new attachment"
Dim content As Byte() = System.Text.Encoding.Default.GetBytes(s)
Dim m As New MemoryStream(content)
attach = New MimeAttachmentStream(m, "file3.txt", TextPlain, QuotedPrintable, "")

' Add it to the message.
msg.Attachments.Add(attach)
attach = Nothing

The message is now created and contains 3 attachments. Send the message.

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// First set the server. smtp1.Server = "mail.test.com"; // Then send. smtp1.Send(msg);

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' First set the server. Smtp1.Server = "mail.test.com" ' Then send. Smtp1.Send(msg)

Compile and run the application. Check the inbox of the email address to which the message was sent. There should be a new message with 3 attachments.