(Node.js) Convert Embedded HTML Images to Multipart/Related CID References

Demonstrates how to convert HTML images that are inline/embedded within the HTML to CID references to multipart/related MIME parts.

Note: This example requires Chilkat v9.5.0.78 or greater.

Install Chilkat for Node.js and Electron using npm at

Chilkat npm packages for Node.js
Chilkat npm packages for Electron
on Windows, Linux, MacOS

var os = require('os');
if (os.platform() == 'win32') {  
  var chilkat = require('@chilkat/ck-node23-win64'); 
} else if (os.platform() == 'linux') {
    if (os.arch() == 'arm') {
        var chilkat = require('@chilkat/ck-node23-linux-arm');
    } else if (os.arch() == 'arm64') {
        var chilkat = require('@chilkat/ck-node23-linux-arm64');
    } else {
        var chilkat = require('@chilkat/ck-node23-linux-x64');
    }
} else if (os.platform() == 'darwin') {
  var chilkat = require('@chilkat/ck-node23-darwin-universal');
}

function chilkatExample() {

    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // This example converts the following email with image data embedded directly in the HTML,
    // to the MIME shown at the bottom of this page.
    // If the HTML contains multiple embedded images, the call to email.ConvertInlineImages will convert all of them.

    // MIME-Version: 1.0
    // Date: Tue, 30 Apr 2019 11:36:34 +0200
    // Message-ID: <E5DB5F8A65D671FB4822B22F5309411838F2FC93@PC0VDL0W013>
    // Content-Type: text/html; charset="windows-1252"
    // Content-Transfer-Encoding: quoted-printable
    // X-Priority: 3 (Normal)
    // From: <admin@chilkatsoft.com>
    // To: Matt <matt@chilkat.io>
    // Subject: Test
    // 
    // <html xmlns=3D"http://www.w3.org/1999/xhtml">
    // <body><p>
    // <img src=3D"data:image/jpeg;base64,/9j/4AAQSkZJRgABAQEA3ADcAAD/2=
    // wBDAAIBAQEBAQIBAQECAgICAgQDAgICAgUEBAMEBgUGBgYFBgYGBwkIBgcJBwYGCAsICQoKCgoK=
    // BggLDAsKDAkKCgr/2wBDAQICAgICAgUDAwUKBwYHCgoKCgoKCgoKCgoKCgoKCgoKCgoKCgoKCgo=
    // ...
    // 4zzS3ww+5/8AyR//2Q=3D=3D" width=3D"58" height=3D"66" alt=3D"" style=3D"bord=
    // er-width:0px;" /></body>
    // </html>

    var email = new chilkat.Email();
    var success = email.LoadEml("qa_data/eml/embedded_html_image.eml");

    email.ConvertInlineImages();
    console.log(email.GetMime());

    // The MIME after moving the image data to a separate MIME sub-part:

    // MIME-Version: 1.0
    // Date: Tue, 30 Apr 2019 11:36:34 +0200
    // Message-ID: <E5DB5F8A65D671FB4822B22F5309411838F2FC93@PC0VDL0W013>
    // Content-Type: multipart/related; boundary="------------020808080005060904000806"
    // X-Priority: 3 (Normal)
    // From: <admin@chilkatsoft.com>
    // To: Matt <matt@chilkat.io>
    // Subject: Test
    // 
    // --------------020808080005060904000806
    // Content-Type: text/html; charset=windows-1252
    // Content-Transfer-Encoding: quoted-printable
    // 
    // <html xmlns=3D"http://www.w3.org/1999/xhtml">
    // </head></head><body><p>
    // <img src=3D"cid:CID-1f73052c-32a7-4abb-8e9d-0afb58c17eed@CHILKATSLICE" widt=
    // h=3D"58" height=3D"66" alt=3D"" style=3D"border-width:0px;" /></body>
    // </html>
    // 
    // 
    // 
    // --------------020808080005060904000806
    // Content-Type: image/jpeg; name="image_95EA3073134C.jpeg"
    // Content-Transfer-Encoding: base64
    // Content-ID: <CID-1f73052c-32a7-4abb-8e9d-0afb58c17eed@CHILKATSLICE>
    // 
    // /9j/4AAQSkZJRgABAQEA3ADcAAD/2wBDAAIBAQEBAQIBAQECAgICAgQDAgICAgUEBAMEBgUGBgYF
    // BgYGBwkIBgcJBwYGCAsICQoKCgoKBggLDAsKDAkKCgr/2wBDAQICAgICAgUDAwUKBwYHCgoKCgoK
    // ...
    // 5bmGF7e42pOwUxrFNEQOcLGw6vX2Yv7NfxbWLYfB67s84vrf/wCLoor8r424ZwGYZkqlSUk+VLRr
    // /Jn2mS8QYzC0Woxi9eqf+aGr+zX8XUyW8K9/+f8Ag/8AjlO/4Zs+Ln/Qqf8Ak/b/APxyiivkXwPl
    // H88/vj/8ifUR4zzS3ww+5/8AyR//2Q==
    // 
    // --------------020808080005060904000806--

}

chilkatExample();