Chilkat Email Class Overview

The Chilkat.Email class represents a complete email message. It contains the message headers, sender and recipient fields, subject, body content, attachments, embedded HTML resources, attached messages, and security-related information such as S/MIME signing and encryption status.

The class is used to create, inspect, modify, load, save, and prepare email messages. It is typically used together with Chilkat mail transport classes, such as MailMan or Imap, which handle sending, receiving, and downloading messages.

Primary Purpose

Use Chilkat.Email when your application needs to:

• Build a new email message.
• Set the sender, recipients, subject, and body.
• Add plain-text and HTML bodies.
• Add file, string, byte-array, or BinData attachments.
• Embed related HTML resources such as images or stylesheets.
• Load an existing .eml or MIME message.
• Inspect headers, recipients, attachments, and MIME parts.
• Save an email as EML, MIME, or XML.
• Work with S/MIME signed or encrypted email.
• Process delivery status notifications and multipart reports.

Message Headers and Addressing

The class provides properties and methods for working with common email header fields.

Common sender and addressing properties include:

Recipients are added using methods such as:

Recipient counts are available through NumTo, NumCC, and NumBcc.

Custom headers can be added with AddHeaderField or AddHeaderField2. Existing headers can be read with GetHeaderField, enumerated by index, or removed with RemoveHeaderField.

Email Bodies

An email may contain a plain-text body, an HTML body, or multiple alternative body formats.

The Body property provides convenient access to the body. If the email contains both HTML and plain text, Body returns the HTML body.

For more precise control, use:

The class also supports iCalendar alternative bodies through AddiCalendarAlternativeBody, which is useful for meeting requests and calendar invitations.

Character Sets and Language Handling

Chilkat.Email includes charset-related properties for controlling how text is represented in MIME.

Important members include:

Setting Charset can update both the MIME headers and, when possible, the HTML META charset information so that the message body and headers agree.

Attachments

The class provides extensive attachment support. Attachments can be added from files, strings, byte arrays, or BinData.

Common attachment methods include:

The OverwriteExisting property controls whether saved attachments overwrite existing files or are automatically renamed to avoid collisions.

Related Items for HTML Email

HTML email often includes embedded images, stylesheets, or other resources referenced from the HTML body. These are called related items. They are part of the message, but they are not treated as ordinary attachments because their purpose is to render the HTML content.

Related items are commonly used for inline images referenced by cid: URLs or by filenames in the HTML.

Useful members include:

The ConvertInlineImages method can convert images embedded directly inside HTML into proper MIME related parts referenced by CID.

Loading and Saving Email

Chilkat.Email can load and save complete email messages in multiple formats.

Loading an email replaces the current contents of the object, including recipients and headers.

MIME Inspection and Processing

The class exposes many methods for inspecting MIME structure directly. This is useful when working with complex messages, custom MIME parts, reports, embedded messages, or partially downloaded messages.

Examples include:

Content-type matching can use exact values such as text/plain or wildcarded values such as text/ or .

Embedded Messages and Digests

Some email clients attach forwarded messages as embedded message/rfc822 parts. Chilkat.Email can detect and retrieve these attached messages.

Useful members include:

The class also supports multipart digest messages through NumDigests and GetDigestEmail.

Delivery Reports and Multipart Reports

Chilkat.Email can process delivery status notifications and other multipart/report messages.

Useful members include:

These methods are useful for analyzing bounce messages, delivery failures, feedback reports, and other server-generated email reports.

S/MIME Signing and Encryption

The class supports S/MIME signing, encryption, decryption, and signature validation.

Sending Signed or Encrypted Email

Receiving Signed or Encrypted Email

The class can also use RSA-OAEP encryption options through OaepPadding, OaepHash, and OaepMgfHash.

Password-Based AES Encryption

In addition to S/MIME, the class includes Chilkat-specific password-based AES encryption:

This is not certificate-based S/MIME encryption. Both sender and receiver must use Chilkat and must know the same password.

Mail Merge and Replacement Patterns

Chilkat.Email includes a simple mail-merge style replacement feature.

Use SetReplacePattern to define pattern/replacement pairs. During sending, Chilkat can replace those patterns in headers and body content.

Useful members include:

Pattern replacement occurs during mail sending or MIME rendering by the mail-sending class. Methods such as SaveEml and GetMime do not apply replacement patterns.

Specialized Message Features

The class also supports several specialized workflows:

Error Information

Most Chilkat methods return true for success and false for failure. When a method fails, check:

email.LastErrorText

LastErrorText provides detailed diagnostic information about the most recent method or property call. It is often useful even when a method succeeds, because it can contain additional details about what occurred internally.

Relationship to MailMan, IMAP, and POP3

Chilkat.Email represents the message itself. It does not perform SMTP, POP3, or IMAP communication on its own.

Typical usage looks like this:

For example, an application may use Imap to download a message, then use Email to inspect its attachments, body, headers, signatures, or MIME structure.

Summary

Chilkat.Email is the central Chilkat class for working with email message content and structure. It provides high-level features for ordinary email composition, plus lower-level access to MIME parts, headers, attachments, related items, embedded messages, delivery reports, and S/MIME security.

Use this class whenever your application needs to build, parse, modify, save, inspect, sign, encrypt, decrypt, or otherwise work with an email message.