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
EIQYEJwQCJQYCJwYCM6clL2Ee5wpGIwhEK0YANatpdalnHMYCKUhCJQYAKUYAM6Ec5QhCJwhCPfW
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--------------080707010302060306060800--

Download Chilkat MIME ActiveX

uses
    Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
    Dialogs, StdCtrls,
    CHILKATMIMELib_TLB,
    OleCtrls;

...

procedure TForm1.Button1Click(Sender: TObject);
var
mime: CHILKATMIMELib_TLB.IChilkatMime;
success: Integer;
part2: CHILKATMIMELib_TLB.IChilkatMime;
filename: String;
name: String;

begin
mime := CoChilkatMime.Create();

success := mime.UnlockComponent('Anything for 30-day trial.');
if (success = 0) then
  begin
    Memo1.Lines.Add(mime.LastErrorText);
    Exit;
  end;

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

success := mime.LoadMimeFile('sampleMime2.txt');
if (success = 0) then
  begin
    Memo1.Lines.Add(mime.LastErrorText);
    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 := mime.GetPart(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 := part2.GetHeaderFieldAttribute('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: ' + part2.Filename);

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

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

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

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

ShowMessage('Finished.');


end;