public string GetHtmlAndRelatedFilesInMemory(
	string virtualPathPrefix
)

Public Function GetHtmlAndRelatedFilesInMemory ( 
	virtualPathPrefix As String
) As String

using System;
using MailBee.Mime;

class Sample
{
    static void UploadToExternalStorage(string webPath, byte[] bytes)
    {
        // This method must upload 'bytes' to some location which is also visible via web as 'webPath'.
    }

    static void Main(string[] args)
    {
        // Load the message from file.
        MailMessage msg = new MailMessage();
        msg.LoadMessage(@"C:\Temp\test.eml");

        // You'll then pass 'body' value to some kind of a browser or webview control.
        // 'body' will have links like <IMG SRC="cid:my_first_img"> and <IMG SRC="cid:my_second_img">
        // look like <IMG SRC="https://domain.com/attach_1"> and <IMG SRC="https://domain.com/attach_2">
        string body = msg.GetHtmlAndRelatedFilesInMemory("https://domain.com/attach_");

        foreach (Attachment attach in msg.Attachments)
        {
            if (!string.IsNullOrEmpty(attach.SavedAs))
            {
                string webPath = attach.SavedAs; // e.g. https://domain.com/attach_1
                byte[] bytes = attach.GetData();

                UploadToExternalStorage(webPath, bytes);
            }
        }
    }
}

Imports System
Imports MailBee.Mime

Class Sample
    Shared Sub UploadToExternalStorage(ByVal webPath As String, ByVal bytes As Byte())
        ' This method must upload 'bytes' to some location which is also visible via web as 'webPath'.
    End Sub

    Shared Sub Main(ByVal args As String())
        ' Load the message from file.
        Dim msg As New MailMessage()
        msg.LoadMessage("C:\Temp\test.eml")

        ' You'll then pass 'body' value to some kind of a browser or webview control.
        ' 'body' will have links like <IMG SRC="cid:my_first_img"> and <IMG SRC="cid:my_second_img">
        ' look like <IMG SRC="https://domain.com/attach_1"> and <IMG SRC="https://domain.com/attach_2">
        Dim body As String = msg.GetHtmlAndRelatedFilesInMemory("https://domain.com/attach_")

        For Each attach As Attachment In msg.Attachments
            If Not String.IsNullOrEmpty(attach.SavedAs) Then
                Dim webPath As String = attach.SavedAs
                ' e.g. https://domain.com/attach_1
                Dim bytes As Byte() = attach.GetData()

                UploadToExternalStorage(webPath, bytes)
            End If
        Next
    End Sub
End Class