Delphi ActiveX

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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var
success: Integer;
email: TChilkatEmail;

begin
success := 0;

//  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.

email := TChilkatEmail.Create(Self);
email.Subject := 'Convert inline images';

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

Memo1.Lines.Add('NumRelatedItems before = ' + IntToStr(email.NumRelatedItems));

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

success := email.ConvertInlineImages();
if (success = 0) then
  begin
    Memo1.Lines.Add(email.LastErrorText);
    Exit;
  end;

Memo1.Lines.Add('NumRelatedItems after = ' + IntToStr(email.NumRelatedItems));