(Go) Rename Email Attachments After Adding

Demonstrates how to rename email attachments after adding but before sending.

Chilkat Go Downloads Go Package for Windows, MacOS, Linux, Alpine Linux, Solaris

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

    mailman := chilkat.NewMailMan()

    mailman.SetSmtpHost("smtp.my-mail-server.com")
    mailman.SetSmtpUsername("MY_SMTP_USERNAME")
    mailman.SetSmtpPassword("MY_SMTP_PASSWORD")
    mailman.SetSmtpSsl(true)
    mailman.SetSmtpPort(465)

    email := chilkat.NewEmail()

    email.SetSubject("This is a test")
    email.SetBody("This is a test")
    email.SetFrom("Chilkat Support <support@chilkatsoft.com>")
    success := email.AddTo("Chilkat Admin","admin@chilkatsoft.com")
    // To add more recipients, call AddTo, AddCC, or AddBcc once per recipient.

    // Add some attachments.
    // The AddFileAttachment method returns the value of the content-type it chose for the attachment.
    contentType := email.AddFileAttachment("qa_data/jpg/starfish.jpg")
    if email.LastMethodSuccess() != true {
        fmt.Println(email.LastErrorText())
        mailman.DisposeMailMan()
        email.DisposeEmail()
        return
    }

    contentType = email.AddFileAttachment("qa_data/pdf/fishing.pdf")
    if email.LastMethodSuccess() != true {
        fmt.Println(email.LastErrorText())
        mailman.DisposeMailMan()
        email.DisposeEmail()
        return
    }

    // If we save the email to a .eml, we can examine in a text editor.
    success = email.SaveEml("qa_output/e1.eml")
    if success == false {
        fmt.Println(email.LastErrorText())
        fmt.Println("Failed to save .eml")
        mailman.DisposeMailMan()
        email.DisposeEmail()
        return
    }

    // We see the following in the e1.eml
    // Notice that Chilkat replaced the full path with just the filename.
    // The full local path is not part of the email that gets sent..

    // ...
    // --------------020807050607070004010609
    // Content-Type: image/jpeg; name="starfish.jpg"
    // Content-Transfer-Encoding: base64
    // Content-Disposition: attachment; filename="starfish.jpg"
    // 
    // ...
    // --------------020807050607070004010609
    // Content-Type: application/pdf; name="fishing.pdf"
    // Content-Transfer-Encoding: base64
    // Content-Disposition: attachment; filename="fishing.pdf"
    // ...

    // Before sending, each filename can be changed within the email object.
    // For example:
    success = email.SetAttachmentFilename(0,"orange_starfish.jpg")
    success = email.SetAttachmentFilename(1,"tuna_fishing.pdf")

    // Look at the new MIME source of the email in a  text editor...
    success = email.SaveEml("qa_output/e2.eml")
    if success == false {
        fmt.Println(email.LastErrorText())
        fmt.Println("Failed to save .eml")
        mailman.DisposeMailMan()
        email.DisposeEmail()
        return
    }

    // You'll see this:

    // ...
    // --------------020807050607070004010609
    // Content-Type: image/jpeg; name="orange_starfish.jpg"
    // Content-Transfer-Encoding: base64
    // Content-Disposition: attachment; filename="orange_starfish.jpg"
    // 
    // ...
    // --------------020807050607070004010609
    // Content-Type: application/pdf; name="tuna_fishing.pdf"
    // Content-Transfer-Encoding: base64
    // Content-Disposition: attachment; filename="tuna_fishing.pdf"
    // ...

    // Send the email with the updated filenames..
    success = mailman.SendEmail(email)
    if success != true {
        fmt.Println(mailman.LastErrorText())
        mailman.DisposeMailMan()
        email.DisposeEmail()
        return
    }

    success = mailman.CloseSmtpConnection()
    if success != true {
        fmt.Println("Connection to SMTP server not closed cleanly.")
    }

    fmt.Println("Mail with attachments sent!")

    mailman.DisposeMailMan()
    email.DisposeEmail()