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Go

Attach a File with an Explicit Content Type

See more Email Object Examples

Demonstrates the Chilkat Email.AddFileAttachment2 method, which attaches a file from the filesystem and lets you explicitly specify its content type rather than having Chilkat infer it from the file extension. This example attaches a binary file as application/octet-stream.

Background: Extension-based type detection is convenient but not always right — a file may have an unusual or missing extension, or you may need a very specific MIME type for the recipient to process it correctly. Specifying the content type explicitly removes the guesswork. application/octet-stream is the generic "arbitrary binary data" type, a safe default that tells the client to treat the attachment as an opaque download rather than trying to render it.

Chilkat Go Downloads

Go
    success := false

    //  Demonstrates the AddFileAttachment2 method, which attaches a file and lets you
    //  explicitly specify its content type instead of letting Chilkat infer it.

    email := chilkat.NewEmail()
    email.SetSubject("Email with a file attachment")
    email.SetBody("Please see the attached file.")

    //  Attach a file, explicitly specifying the content type.
    success = email.AddFileAttachment2("qa_data/attachments/data.bin","application/octet-stream")
    if success == false {
        fmt.Println(email.LastErrorText())
        email.DisposeEmail()
        return
    }

    fmt.Println("NumAttachments = ", email.NumAttachments())

    //  Note: The path "qa_data/attachments/data.bin" is a relative local filesystem path,
    //  relative to the current working directory of the running application.

    email.DisposeEmail()