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JavaScript

Attach an Email to Another Email

See more Email Object Examples

Demonstrates the Chilkat Email.AttachEmail method, which attaches a copy of another email to this email object. The attached email is encapsulated in a message/rfc822 subpart. Because a copy is attached, later changes to the source email do not affect the embedded message. This example attaches one email to another.

Background: "Forward as attachment" produces exactly this structure: the original message is embedded whole as a message/rfc822 part rather than quoted into the body. This preserves the original's headers and formatting intact, which matters for forwarding to a mailbox that will re-parse it, or for reporting spam/phishing with the original evidence attached. Such parts are counted by NumAttachedMessages.
Note
This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.
JavaScript
var success = false;

//  Demonstrates the AttachEmail method, which attaches a copy of another email to this email
//  object.  The attached email is encapsulated in a message/rfc822 subpart.

var innerEmail = new CkEmail();
innerEmail.Subject = "Original message";
innerEmail.From = "alice@example.com";
innerEmail.Body = "This is the original message being forwarded.";

var email = new CkEmail();
email.Subject = "FW: Original message";
email.From = "bob@example.com";
email.Body = "See the attached original email.";

//  Attach a copy of the inner email as a message/rfc822 part.

success = email.AttachEmail(innerEmail);
if (success == false) {
    console.log(email.LastErrorText);
    return true;
}

console.log("NumAttachedMessages = " + email.NumAttachedMessages);