Sample code for 30+ languages & platforms
PureBasic

Open a Persistent SMTP Connection

See more SMTP Examples

Demonstrates the Chilkat MailMan.OpenSmtpConnection method, which explicitly opens a connection to the SMTP server and authenticates if a username and password, OAuth2 token, or other applicable settings have been provided. This example opens the connection, notes where sending would occur, and closes it.

Background: By default, sending a single email opens a connection, sends, and closes it. When sending many messages, that per-message overhead adds up. Explicitly calling OpenSmtpConnection once, sending in a loop, then CloseSmtpConnection keeps a single authenticated session open for the whole batch — substantially faster and gentler on the server than reconnecting each time.

Chilkat PureBasic Downloads

PureBasic
IncludeFile "CkMailMan.pb"

Procedure ChilkatExample()

    success.i = 0

    ;  Demonstrates the MailMan.OpenSmtpConnection method, which explicitly opens a connection
    ;  to the SMTP server and authenticates if credentials (or an OAuth2 token) have been
    ;  provided.

    mailman.i = CkMailMan::ckCreate()
    If mailman.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ;  Configure the SMTP server connection.
    CkMailMan::setCkSmtpHost(mailman, "smtp.example.com")
    CkMailMan::setCkSmtpPort(mailman, 465)
    CkMailMan::setCkSmtpSsl(mailman, 1)
    CkMailMan::setCkSmtpUsername(mailman, "user@example.com")
    CkMailMan::setCkSmtpPassword(mailman, "myPassword")

    ;  Explicitly open (and authenticate) the SMTP connection.

    success = CkMailMan::ckOpenSmtpConnection(mailman)
    If success = 0
        Debug CkMailMan::ckLastErrorText(mailman)
        CkMailMan::ckDispose(mailman)
        ProcedureReturn
    EndIf

    Debug "SMTP connection opened."

    ;  ... send one or more emails here ...

    ;  Close the connection when done.
    success = CkMailMan::ckCloseSmtpConnection(mailman)
    If success = 0
        Debug CkMailMan::ckLastErrorText(mailman)
        CkMailMan::ckDispose(mailman)
        ProcedureReturn
    EndIf



    CkMailMan::ckDispose(mailman)


    ProcedureReturn
EndProcedure