Generic solution for using images in html part of email it’s build in images as attachment and use attachment ID as SRC of image.
something like:
<img src="cid:2.jpg" alt="Red dot" />
In this case all client mail viewers must show email as it's should be.
Here is part of my old project that add all html images into attachments from 'file names' into corrent identifiers. It's not optimal sourses but you can get main idia from it.
uses
IdBaseComponent,
IdComponent, IdTCPConnection, IdTCPClient, IdExplicitTLSClientServerBase,
IdMessageClient, IdSMTPBase, IdSMTP, IdIOHandler, IdIOHandlerSocket,
IdIOHandlerStack, IdSSL, IdSSLOpenSSL,
idMessage, IdAttachment,
idText, IdAttachmentFile, math;
function HtmlDecode (const AStr: String): String;
begin
Result := StringReplace(AStr, ''', '''', [rfReplaceAll]); {Do not Localize}
Result := StringReplace(Result, '"', '"', [rfReplaceAll]); {Do not Localize}
Result := StringReplace(Result, '>', '>', [rfReplaceAll]); {Do not Localize}
Result := StringReplace(Result, '<', '<', [rfReplaceAll]); {Do not Localize}
Result := StringReplace(Result, '&', '&', [rfReplaceAll]); {Do not Localize}
end;
function IsXDigit(Ch : char) : Boolean;
begin
Result := (ch in ['0'..'9']) or (ch in ['a'..'f']) or (ch in ['A'..'F']);
end;
function XDigit(Ch : char) : Integer;
begin
if ch in ['0'..'9'] then
Result := ord(Ch) - ord('0')
else
Result := (ord(Ch) and 15) + 9;
end;
function htoin(value : PChar; len : Integer) : Integer;
var
i : Integer;
begin
Result := 0;
i := 0;
while (i < len) and (Value[i] = ' ') do
i := i + 1;
while (i < len) and (isxDigit(Value[i])) do begin
Result := Result * 16 + xdigit(Value[i]);
i := i + 1;
end;
end;
function htoi2(value : PChar) : Integer;
begin
Result := htoin(value, 2);
end;
function UrlDecode(S : String) : String;
var
I : Integer;
Ch : Char;
begin
Result := '';
I := 1;
while (I <= Length(S)) do begin
Ch := S[I];
if Ch = '%' then begin
Ch := chr(htoi2(@S[I + 1]));
Inc(I, 2);
end
else if Ch = '+' then
Ch := ' ';
Result := Result + Ch;
Inc(I);
end;
end;
procedure TForm3.HandleIMGID(ASourceDir: String;
var AHTMString: String; AMessage: TIDMessage; AParentPart : integer = -1);
var
IMGPos : Integer ;
CurrentPoint : Pchar ;
AFile : String ;
AAttachment : TIdAttachment ;
begin
CurrentPoint := pchar(AHTMString);
IMGPos := 0 ;
while pos('src="', CurrentPoint) <> 0 do begin
IMGPos := IMGPos + pos('src="',CurrentPoint) + 4 ;
CurrentPoint := pchar(AHTMString) + IMGPos ;
if pos('"', CurrentPoint) <> 0 then begin
AFile := copy(AHTMString, IMGPos + 1, pos('"', CurrentPoint) - 1);
AFile := UrlDecode(afile) ;
AFile := StringReplace(AFile, '/', '\', [rfReplaceAll]);
if FileExists(IncludeTrailingBackslash(ASourceDir) + AFile) then
AFile := IncludeTrailingBackslash(ASourceDir) + AFile;
if FileExists(AFile) then begin
AAttachment := TIdAttachmentFile.Create(AMessage.MessageParts, AFile);
AAttachment.FileName := HtmlDecode(ExtractFileName(AFile));
AAttachment.ContentType := 'image/jpeg';
AAttachment.Headers.Add('Content-ID: <' + AAttachment.FileName + '>');
AAttachment.ParentPart := AParentPart;
delete(AHTMString, IMGPos + 1, pos('"', CurrentPoint) - 1);
insert('cid:' + AAttachment.FileName, AHTMString, IMGPos + 1);
end{if};
CurrentPoint := CurrentPoint + min(pos('"', CurrentPoint), 0);
AFile := '';
end{if};
end{while};
end;
procedure TForm3.Button1Click(Sender: TObject);
var
s : string;
xMessage : TIDMessage;
APlainHTML, APlainText, ATextPart, AEmail : TIdText ;
begin
IdSMTP1.Username := 'from@mail.com';
IdSMTP1.Password := 'password';
IdSMTP1.Port := 587;
IdSMTP1.Host := 'hosturl.com';
IdSMTP1.IOHandler := IdSSLIOHandlerSocketOpenSSL1;
IdSMTP1.UseTLS := utUseExplicitTLS;
IdSMTP1.Connect;
xMessage := TIDMessage.Create(self) ;
try
//fill message attributes
xMessage.From.Name := 'from@mail.com';
xMessage.From.Address := 'from@mail.com';
xMessage.Subject := 'Some test subject';
//fill Recipients
xMessage.Recipients.Clear ;
xMessage.Recipients.EMailAddresses := 'recipient@gmail.com';
xMessage.BccList.Clear;
xMessage.ccList.Clear;
//fill message content
xMessage.ContentType := 'multipart/mixed';
AEmail := TIdText.create(xMessage.MessageParts);
AEmail.ContentType := 'multipart/related; type="multipart/alternative"';
ATextPart := TIdText.create(xMessage.MessageParts);
ATextPart.ContentType := 'multipart/alternative';
ATextPart.ParentPart := 0;
APlainText := TIdText.create(xMessage.MessageParts);
APlainText.ContentType := 'text/plain';
APlainText.Body.Text := 'Some plain text of mail';
APlainText.ParentPart := ATextPart.Index;
//load html
APlainHTML := TIdText.create(xMessage.MessageParts);
APlainHTML.ContentType := 'text/html';
APlainHTML.ParentPart := ATextPart.Index;
s := '<html>' + #13#10 +
' <head>' + #13#10 +
' </head>' + #13#10 +
' <body>' + #13#10 +
' <div>' + #13#10 +
' <p>Some text</p>' + #13#10 +
// ' <img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAAHElEQVQI12P4' + #13#10 +
// ' //8/w38GIAXDIBKE0DHxgljNBAAO9TXL0Y4OHwAAAABJRU5ErkJggg==" alt="Red dot" />' + #13#10 +
' <img src="2.jpg" alt="Red dot" />' + #13#10 +
' </div>' + #13#10 +
' </body>' + #13#10 +
'</html>';
HandleIMGID('C:\temp', s, xMessage, 0);
// HandleIMGID(FSettings.TeplateFolder, s, xMessage, 0);
APlainHTML.Body.Text := s;
if IdSMTP1.Authenticate then begin
IdSMTP1.Send(xMessage);
end;
finally
xMessage.Free;
end;
end;
P.S. All images from attachments will not be shown as attached files if it's uses in html part.
