(VB.NET) How to Download Messages in MessageSet One at a Time

If a message set contains a huge number of emails, it's NOT a good idea to try to download all at once into an email bundle using a method such as FetchBundle. It's better to iterate over the messages in the set to download one by one.

Chilkat .NET Downloads Chilkat .NET Framework Chilkat for .NET Core

' 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 using TLS.
imap.Ssl = True
imap.Port = 993
Dim success As Boolean = imap.Connect("imap.example.com")
If (success <> True) Then
    Debug.WriteLine(imap.LastErrorText)
    Exit Sub
End If


' Authenticate
success = imap.Login("email_account_login","email_account_password")
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


' Search for messages and return a set of matching messages.
' (This example will simply search for ALL messages.)
Dim fetchUids As Boolean = True
Dim messageSet As Chilkat.MessageSet = imap.Search("ALL",fetchUids)
If (imap.LastMethodSuccess <> True) Then
    Debug.WriteLine(imap.LastErrorText)
    Exit Sub
End If


Debug.WriteLine("Number of messages = " & messageSet.Count)

Dim i As Integer = 0
While i < messageSet.Count
    Dim email As Chilkat.Email = imap.FetchSingle(messageSet.GetId(i),fetchUids)
    If (imap.LastMethodSuccess <> True) Then
        Debug.WriteLine(imap.LastErrorText)

        Exit Sub
    End If

    Debug.WriteLine(email.From & "; " & email.Subject)


    i = i + 1
End While



Debug.WriteLine("OK")