VB.NET

Download an IMAP Message Set

Demonstrates how to read a set of IMAP emails. VB.NET

Dim success As Boolean = False

' 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
success = imap.Connect("imap.example.com")
If (success = False) Then
    Debug.WriteLine(imap.LastErrorText)
    Exit Sub
End If


' Authenticate
success = imap.Login("email_account_login","email_account_password")
If (success = False) Then
    Debug.WriteLine(imap.LastErrorText)
    Exit Sub
End If


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


' Search for messages with the word "test" in the subject.
Dim fetchUids As Boolean = True

Dim messageSet As New Chilkat.MessageSet
success = imap.QueryMbx("Subject test",fetchUids,messageSet)
If (success = False) Then
    Debug.WriteLine(imap.LastErrorText)
    Exit Sub
End If


' Download the messages in a single call to FetchMsgSet.
' 
' This only makes sense if the number of emails to be downloaded is not too large.  
' For example, you wouldn't want to download 10000 emails in a single call to FetchMsgSet.
' Why? For two reasons:  (1) It could potentially cause an out-of-memory condition, and 
' (2) it would take an extremely large amount of time.  The longer the amount of time,
' the greater the likelihood of some kind of external networking or server problem occuring,
' and if it happens, then you would need to re-download everything from the beginning again.
' For large numbers of emails, it's better to loop over the emails in the message set
' and download/process one at a time as shown here: Download IMAP Messages One at a Time
' Downloading one message at a time makes it possible to resume the downloads rather than restart the entire operation all over again.

' If the message set is reasonable in size, you can download all at once using FetchMsgSet:

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

Dim bundle As New Chilkat.EmailBundle
Dim headersOnly As Boolean = False
success = imap.FetchMsgSet(headersOnly,messageSet,bundle)
If (success = False) Then
    Debug.WriteLine(imap.LastErrorText)
    Exit Sub
End If


' Display the Subject and From of each email.
Dim email As New Chilkat.Email
Dim i As Integer = 0
Dim numEmails As Integer = bundle.MessageCount
While i < numEmails
    bundle.EmailAt(i,email)

    Debug.WriteLine(email.GetHeaderField("Date"))
    Debug.WriteLine(email.Subject)
    Debug.WriteLine(email.From)
    Debug.WriteLine("--")
    i = i + 1
End While