(Delphi DLL) Parse MIME Header Fields

Demonstrates how to parse MIME header fields, including Content-Type, Content-Disposition, and Content-Transfer-Encoding.

This example uses a MIME test file located at http://www.chilkatsoft.com/testData/sampleMime2.txt. It contains the following MIME:

Content-Type: multipart/mixed;
 boundary="------------080707010302060306060800";

This is a multi-part message in MIME format.

--------------080707010302060306060800
Content-Type: text/plain
Content-Transfer-Encoding: 7bit

This is the plain-text body.
--------------080707010302060306060800
Content-Disposition: attachment; filename="starfish.gif";
Content-Transfer-Encoding: base64
Content-Type: image/gif; name="starfish.gif";

R0lGODlhIAAgAPcAAP///+/v7/f39+/n5/fv7//39/fn597OzufW1tbGxs69vffe3u/W1salpZQQ
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--------------080707010302060306060800--

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Mime;

...

procedure TForm1.Button1Click(Sender: TObject);
var
mime: HCkMime;
success: Boolean;
part2: HCkMime;
filename: PWideChar;
name: PWideChar;

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

mime := CkMime_Create();

// Load the sampleMime2.txt file into the MIME object.
// (This file is available at http://www.chilkatsoft.com/testData/sampleMime2.txt )

success := CkMime_LoadMimeFile(mime,'sampleMime2.txt');
if (success = False) then
  begin
    Memo1.Lines.Add(CkMime__lastErrorText(mime));
    Exit;
  end;

// The GIF image is the 2nd sub-part located directly under the
// top-level MIME node.  Indexing begins at 0, therefore the 2nd
// sub-part is at index 1.

part2 := CkMime_GetPart(mime,1);

// -------------------------------
// Content-Disposition
// -------------------------------
// In this example, the Content-Disposition header field
// contains this value:
// attachment; filename="starfish.gif"

// To get the "filename", call GetHeaderFieldAttribute
// Header field names and attribute names are case insensitive.
filename := CkMime__getHeaderFieldAttribute(part2,'Content-Disposition','filename');
Memo1.Lines.Add('Filename: ' + filename);

// Because the "filename" is so often accessed, it is also available
// by accessing the "Filename" property:
Memo1.Lines.Add('Filename: ' + CkMime__filename(part2));

// The disposition (without attributes) which in this case 
// is the string "attachment" is accessed via the Disposition property:
Memo1.Lines.Add('Disposition: ' + CkMime__disposition(part2));

// To get the full value of the Content-Disposition header field,
// call GetHeaderField.
Memo1.Lines.Add('Content-Disposition: ' + CkMime__getHeaderField(part2,'Content-Disposition'));

// -------------------------------
// Content-Type
// -------------------------------
// In this example, the Content-Type header field
// contains this value:
// image/gif; name="starfish.gif"

// To get the "name", call GetHeaderFieldAttribute
name := CkMime__getHeaderFieldAttribute(part2,'Content-Type','name');
Memo1.Lines.Add('Content-Type name: ' + name);

// Because the "name" is so often accessed, it is also available
// by accessing the "Name" property:
Memo1.Lines.Add('Content-Type name: ' + CkMime__name(part2));

// The content-type without attributes is available in the
// ContentType property:
Memo1.Lines.Add('Content-Type: ' + CkMime__contentType(part2));

// To get the full value of the Content-Type header field,
// call GetHeaderField.
Memo1.Lines.Add('Content-Type: ' + CkMime__getHeaderField(part2,'Content-Type'));

// -------------------------------
// Content-Transfer-Encoding
// -------------------------------

// The Encoding property contains the value of the
// Content-Transfer-Encoding property. 
// Calling GetHeaderField("Content-Transfer-Encoding") is
// equivalent to accessing the Encoding property:
Memo1.Lines.Add('Content-Transfer-Encoding: ' + CkMime__encoding(part2));
Memo1.Lines.Add('Content-Transfer-Encoding: ' + CkMime__getHeaderField(part2,'Content-Transfer-Encoding'));

CkMime_Dispose(part2);

Memo1.Lines.Add('Finished.');

CkMime_Dispose(mime);

end;