(VB.NET) Iterate MIME Parts of an Email

Demonstrates how to iterate over the MIME sub-parts of an email, and retrieve the content of each MIME sub-part body.

Note: This example requires some new features added to Chilkat v9.5.0.95.

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

' See the following Chilkat post to Quickly Understand Email MIME

Dim email As New Chilkat.Email

Dim success As Boolean = email.LoadEml("qa_data/eml/sample.eml")
If (success = False) Then
    Debug.WriteLine("Failed to load .eml")
    Exit Sub
End If


Dim sbContentType As New Chilkat.StringBuilder
Dim caseSensitive As Boolean = False

' Get the total number of non-multipart MIME sub-parts.
' (This is a simple way of iterating over all the MIME leaf parts regardless of the MIME tree structure)
Dim inlineOnly As Boolean = False
Dim excludeAttachments As Boolean = False
Dim searchSpec As String = "*/*"

Dim numParts As Integer = email.GetNumPartsOfType(searchSpec,inlineOnly,excludeAttachments)
Dim i As Integer = 0
While i < numParts
    ' What is the Content-Type of this MIME part?
    sbContentType.Append(email.GetNthContentType(i,searchSpec,inlineOnly,excludeAttachments))
    If (sbContentType.StartsWith("text/",caseSensitive) = True) Then
        ' Get the text body of this MIME part.
        Dim textBody As String = email.GetNthTextPartOfType(i,searchSpec,inlineOnly,excludeAttachments)
        Debug.WriteLine("Got text body for " & sbContentType.GetAsString())
    Else
        If (sbContentType.ContentsEqual("message/rfc822",caseSensitive) = True) Then
            ' If the Content-Type is message/rfc822, then the MIME body for this part contains a full embedded MIME messages.
            ' Your application could load it into a Chilkat email object and recursively process...
            Dim attachedEmail As New Chilkat.Email
            Dim bdMime As New Chilkat.BinData
            email.GetNthBinaryPartOfTypeBd(i,searchSpec,inlineOnly,excludeAttachments,bdMime)
            attachedEmail.SetFromMimeBd(bdMime)
            ' Now your app can recursively process the attachedEmail...
        Else
            ' Get the bytes of this MIME body part.
            Dim bd As New Chilkat.BinData
            email.GetNthBinaryPartOfTypeBd(i,searchSpec,inlineOnly,excludeAttachments,bd)
            Debug.WriteLine("Got binary body for " & sbContentType.GetAsString() & " numBytes = " & bd.NumBytes)
        End If

    End If

    sbContentType.Clear()
    i = i + 1
End While