@independentsoft/msg/examples/add-attachment.js

Outlook .msg file module

import * as msg from './../independentsoft/msg.js';
import * as fs from 'fs';

const buffer = fs.readFileSync("e:\\test.pdf");
let attachment = new msg.Attachment(buffer);
attachment.fileName = "test.pdf";
attachment.displayName = "test.pdf";

let message = new msg.Message();
message.subject = "Test";
message.body = "Body text";
message.messageFlags.push(msg.MessageFlag.UNSENT);
message.storeSupportMasks.push(msg.StoreSupportMask.CREATE);
message.attachments.push(attachment)

fs.writeFileSync("e:\\message.msg", message.toBytes());