(VB.NET) Load .eml and Examine the Structure, Attachments, and Related Items

Demonstrates how to load examine the MIME structure of a .eml, and also examine the attachment and related item filenames, attached messages, and multipart/report and DSN information.

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

Dim emlPath As String = "C:/AAWorkarea/beatrix/roesner.eml"

Dim mime As New Chilkat.Mime

Dim success As Boolean = mime.LoadMimeFile(emlPath)
If (success <> True) Then
    Debug.WriteLine(mime.LastErrorText)
    Exit Sub
End If


Debug.WriteLine("---- MIME structure ----")
Debug.WriteLine(mime.GetStructure("text"))
Debug.WriteLine("------------------------")

Dim email As New Chilkat.Email
success = email.LoadEml(emlPath)

' Was this a signed and/or encrypted email?
' If so, then loading the .eml automatically unwraps
' (i.e. verifies signatures and decrypts) and the resultant
' email is what existed prior to signing/encrypting.
Debug.WriteLine("Email was Signed: " & email.ReceivedSigned)
Debug.WriteLine("Email was Encrypted: " & email.ReceivedEncrypted)
If (email.ReceivedSigned = True) Then
    Debug.WriteLine("Signature(s) valid = " & email.SignaturesValid)
End If

If (email.ReceivedEncrypted = True) Then
    Debug.WriteLine("Decrypted successfully = " & email.Decrypted)
End If


Dim i As Integer = 0
Dim numAttach As Integer = email.NumAttachments
Debug.WriteLine("Number of attachments = " & numAttach)

While i < numAttach
    Debug.WriteLine("---- Attachment " & i)

    ' Examine the filename (if any)
    Debug.WriteLine("filename: " & email.GetAttachmentFilename(i))
    ' Examine the content-ID (if any)
    Debug.WriteLine("Content-ID: " & email.GetAttachmentContentID(i))
    ' Examine the content-type
    Debug.WriteLine("Content-Type: " & email.GetAttachmentContentType(i))
    ' Examine the content-disposition
    Debug.WriteLine("Content-Disposition" & email.GetAttachmentHeader(i,"content-disposition"))
    ' Examine the attachment size:
    Debug.WriteLine("Size (in bytes) of the attachment: " & email.GetAttachmentSize(i))

    i = i + 1
End While
Debug.WriteLine("--")

' Now for the related items.

' Note: A MIME sub-part can potentially be both a related item AND an attachment.
' The typical case is when the item is contained under the multipart/related enclosure and 
' the item also has a "Content-Disposition" header indicating "attachment".
' The location within multipart/related makes it a "related item", yet the Content-Disposition can also make it semantically an attachment.
' Related items and attachments are not necessarily mutually exclusive.


Dim numRelated As Integer = email.NumRelatedItems
Debug.WriteLine("Number of related items = " & numRelated)
i = 0
While i < numRelated
    Debug.WriteLine("---- Related Item " & i)

    ' Examine the filename (if any)
    Debug.WriteLine("filename: " & email.GetRelatedFilename(i))
    ' Examine the content-ID (if any)
    Debug.WriteLine("Content-ID: " & email.GetRelatedContentID(i))
    ' Examine the content-type
    Debug.WriteLine("Content-Type: " & email.GetRelatedContentType(i))
    ' Examine the content-location (if any)
    Debug.WriteLine("Content-Location" & email.GetRelatedContentLocation(i))

    i = i + 1
End While

' The email could also have attached messages.
' An attached message is another email that was attached to this email.
Dim numAttachedMessages As Integer = email.NumAttachedMessages
Debug.WriteLine("Number of attached messages = " & numAttachedMessages)
i = 0
While i < numAttachedMessages
    Debug.WriteLine("---- Attached message " & i)

    ' Examine the attached email
    Dim em As Chilkat.Email = email.GetAttachedMessage(i)
    Debug.WriteLine("from: " & em.From)
    Debug.WriteLine("subject: " & em.Subject)

    i = i + 1
End While

' An email could also be a multipart/report email. 
' This is a DSN (Delivery Status Notification)
' The NumReports property indicates how many "reports" exist.
Dim numReports As Integer = email.NumReports
i = 0
Debug.WriteLine("Number of reports = " & numReports)
i = 0
While i < numReports
    Debug.WriteLine("---- Report " & i)
    ' Get the raw report data...
    Debug.WriteLine(email.GetReport(i))
    i = i + 1
End While

' If the email is a multipart/report, then the information
' from the message/delivery-status part of the email can be retrieved:
If (email.IsMultipartReport() = True) Then

    Debug.WriteLine("--- Delivery Status Information:")
    Debug.WriteLine("Status: " & email.GetDeliveryStatusInfo("Status"))
    Debug.WriteLine("Action: " & email.GetDeliveryStatusInfo("Action"))
    Debug.WriteLine("Reporting-MTA: " & email.GetDeliveryStatusInfo("Reporting-MTA"))

    Dim sa As Chilkat.StringArray = email.GetDsnFinalRecipients()
    Dim numFinalRecipients As Integer = sa.Count
    i = 0
    While i < numFinalRecipients
        Debug.WriteLine("final recipient: " & sa.GetString(i))
        i = i + 1
    End While

End If