(VB.NET) Read IMAP Email Headers

Call FetchHeaders to download only the email headers.

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

Dim imap As New Chilkat.Imap

' Connect to an IMAP server.
' Use TLS
imap.Ssl = True
imap.Port = 993
Dim success As Boolean = imap.Connect("imap.someMailServer.com")
If (success <> True) Then
    Debug.WriteLine(imap.LastErrorText)
    Exit Sub
End If


' Login
success = imap.Login("****","****")
If (success <> True) Then
    Debug.WriteLine(imap.LastErrorText)
    Exit Sub
End If


' Select an IMAP mailbox
success = imap.SelectMailbox("Inbox")
If (success <> True) Then
    Debug.WriteLine(imap.LastErrorText)
    Exit Sub
End If



Dim messageSet As Chilkat.MessageSet
' We can choose to fetch UIDs or sequence numbers.
Dim fetchUids As Boolean = True
' Get the message IDs of all the emails in the mailbox
messageSet = imap.Search("ALL",fetchUids)
If (imap.LastMethodSuccess <> True) Then
    Debug.WriteLine(imap.LastErrorText)
    Exit Sub
End If


' When downloading headers, each email object contains
' (obviously) the headers, but the body will be missing.
' Also, attachments will not be included.  However, it is
' possible to get information about the attachments
' as well as the complete size of the email.
Dim bundle As Chilkat.EmailBundle
bundle = imap.FetchHeaders(messageSet)
If (imap.LastMethodSuccess <> True) Then

    Debug.WriteLine(imap.LastErrorText)
    Exit Sub
End If


' Loop over the email objects and display information
' about each:
Dim i As Integer
For i = 0 To bundle.MessageCount - 1
    Dim email As Chilkat.Email
    email = bundle.GetEmail(i)

    ' Display the From and Subject
    Debug.WriteLine(email.From)
    Debug.WriteLine(email.Subject)

    ' Display the recipients:
    Dim j As Integer
    Dim name As String
    Dim addr As String
    For j = 0 To email.NumTo - 1
        name = email.GetToName(j)
        addr = email.GetToAddr(j)
        Debug.WriteLine(name & ", " & addr)
    Next
    For j = 0 To email.NumCC - 1
        name = email.GetCcName(j)
        addr = email.GetCcAddr(j)
        Debug.WriteLine(name & ", " & addr)
    Next

    ' Show the total size of the email, including body and attachments:
    Debug.WriteLine(email.Size)

    ' When a full email is downloaded, we would use the
    ' email.NumAttachments property in conjunction with the
    ' email.GetMailAttach* methods.
    ' However, when an email object contains only the header,
    ' we need to access the attachment info differently:
    Dim numAttach As Integer = imap.GetMailNumAttach(email)
    For j = 0 To numAttach - 1
        Debug.WriteLine(imap.GetMailAttachFilename(email,j))
        Dim attachSize As Integer = imap.GetMailAttachSize(email,j)
        Debug.WriteLine("    size = " & attachSize & " bytes")
    Next

    Debug.WriteLine("--")

Next

' Disconnect from the IMAP server.
success = imap.Disconnect()