Swift

Convert Inline Data-URL Images to Related Parts

Demonstrates the Chilkat Email.ConvertInlineImages method, which converts images embedded inline within HTML (as base64 data URLs) into multipart/related MIME parts referenced from the HTML by cid:. This example sets an HTML body containing a data-URL image and converts it.

Background: HTML can embed an image two ways: as a data: URL (the base64 bytes sit right in the src attribute) or as a related part referenced by cid:. Many email clients don't render data: URLs for security reasons, so converting them to proper multipart/related parts — the traditional email way to embed images — greatly improves how reliably the images display.

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Swift


func chilkatTest() {
    var success: Bool = false

    //  Demonstrates the ConvertInlineImages method, which converts images embedded inline within
    //  HTML (as base64 data URLs) into multipart/related MIME parts referenced from the HTML by
    //  CID.

    let email = CkoEmail()!
    email.subject = "Convert inline images"

    //  An HTML body with a base64 data-URL image (a 1x1 PNG).
    email.setHtmlBody(html: "<html><body><img src=\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mP8z8BQDwAEhQGAhKmMIQAAAABJRU5ErkJggg==\"/></body></html>")

    print("NumRelatedItems before = \(email.numRelatedItems.intValue)")

    //  Convert the inline data-URL image(s) to multipart/related parts referenced by CID.

    success = email.convertInlineImages()
    if success == false {
        print("\(email.lastErrorText!)")
        return
    }

    print("NumRelatedItems after = \(email.numRelatedItems.intValue)")

}