(Swift 3,4,5...) Process Large POP3 Mailbox

Demonstrates how to read email from a mailbox that may contain a large number of emails.

Chilkat Downloads for the Swift Programming Language MAC OS X (Cocoa) Objective-C/Swift Libs iOS Objective-C/Swift Libs

func chilkatTest() {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    let mailman = CkoMailMan()!

    mailman.mailHost = "pop.example.com"

    mailman.popUsername = "myLogin"
    mailman.popPassword = "myPassword"

    mailman.mailPort = 995
    mailman.popSsl = true

    // Get the list of UIDLs for all emails in the mailbox.
    var sa: CkoStringArray? = mailman.getUidls()
    if mailman.lastMethodSuccess == false {
        print("\(mailman.lastErrorText!)")
        return
    }

    var i: Int
    var numEmails: Int = sa!.count.intValue
    if numEmails == 0 {
        print("Mailbox is empty")
        return
    }

    var chunkSize: Int = 6

    // Download the emails in chunks of 6 emails each.
    var chunkBeginIdx: Int = 0
    var chunkEndIdx: Int = chunkSize - 1
    if chunkEndIdx >= numEmails {
        chunkEndIdx = numEmails - 1
    }

    let saChunk = CkoStringArray()!
    while (chunkBeginIdx < numEmails) {

        print("\(chunkBeginIdx) to \(chunkEndIdx)")

        // Build a chunk of UIDLs.
        saChunk.clear()
        for i = chunkBeginIdx; i <= chunkEndIdx; i++ {
            saChunk.append(sa!.getString(i))
        }

        // Log the UIDLs in this chunk...
        var chunkStr: String? = saChunk.saveToText()
        print("\(chunkStr!)")

        // Download this chunk of email from the POP3 server.
        var bundle: CkoEmailBundle? = mailman.fetchMultiple(saChunk)
        if mailman.lastMethodSuccess == false {
            print("\(mailman.lastErrorText!)")
            return
        }

        print("Downloaded \(bundle!.messageCount.intValue) emails.")
        print("----")

        // Process the bundle...
        // (your application's processing code goes here...)

        bundle = nil

        // Get the next chunk...
        chunkBeginIdx = chunkBeginIdx + chunkSize
        chunkEndIdx = chunkEndIdx + chunkSize
        if chunkEndIdx >= numEmails {
            chunkEndIdx = numEmails - 1
        }

    }

    sa = nil

}