(Delphi DLL) Iterate MIME Parts of an Email

Demonstrates how to iterate over the MIME sub-parts of an email, and retrieve the content of each MIME sub-part body.

Note: This example requires some new features added to Chilkat v9.5.0.95.

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, StringBuilder, BinData, Email;

...

procedure TForm1.Button1Click(Sender: TObject);
var
email: HCkEmail;
success: Boolean;
sbContentType: HCkStringBuilder;
caseSensitive: Boolean;
inlineOnly: Boolean;
excludeAttachments: Boolean;
searchSpec: PWideChar;
numParts: Integer;
i: Integer;
textBody: PWideChar;
attachedEmail: HCkEmail;
bdMime: HCkBinData;
bd: HCkBinData;

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

// See the following Chilkat post to Quickly Understand Email MIME

email := CkEmail_Create();

success := CkEmail_LoadEml(email,'qa_data/eml/sample.eml');
if (success = False) then
  begin
    Memo1.Lines.Add('Failed to load .eml');
    Exit;
  end;

sbContentType := CkStringBuilder_Create();
caseSensitive := False;

// Get the total number of non-multipart MIME sub-parts.
// (This is a simple way of iterating over all the MIME leaf parts regardless of the MIME tree structure)
inlineOnly := False;
excludeAttachments := False;
searchSpec := '*/*';

numParts := CkEmail_GetNumPartsOfType(email,searchSpec,inlineOnly,excludeAttachments);
i := 0;
while i < numParts do
  begin
    // What is the Content-Type of this MIME part?
    CkStringBuilder_Append(sbContentType,CkEmail__getNthContentType(email,i,searchSpec,inlineOnly,excludeAttachments));
    if (CkStringBuilder_StartsWith(sbContentType,'text/',caseSensitive) = True) then
      begin
        // Get the text body of this MIME part.
        textBody := CkEmail__getNthTextPartOfType(email,i,searchSpec,inlineOnly,excludeAttachments);
        Memo1.Lines.Add('Got text body for ' + CkStringBuilder__getAsString(sbContentType));
      end
    else
      begin
        if (CkStringBuilder_ContentsEqual(sbContentType,'message/rfc822',caseSensitive) = True) then
          begin
            // If the Content-Type is message/rfc822, then the MIME body for this part contains a full embedded MIME messages.
            // Your application could load it into a Chilkat email object and recursively process...
            attachedEmail := CkEmail_Create();
            bdMime := CkBinData_Create();
            CkEmail_GetNthBinaryPartOfTypeBd(email,i,searchSpec,inlineOnly,excludeAttachments,bdMime);
            CkEmail_SetFromMimeBd(attachedEmail,bdMime);
            // Now your app can recursively process the attachedEmail...
          end
        else
          begin
            // Get the bytes of this MIME body part.
            bd := CkBinData_Create();
            CkEmail_GetNthBinaryPartOfTypeBd(email,i,searchSpec,inlineOnly,excludeAttachments,bd);
            Memo1.Lines.Add('Got binary body for ' + CkStringBuilder__getAsString(sbContentType) + ' numBytes = ' + IntToStr(CkBinData_getNumBytes(bd)));
          end;
      end;
    CkStringBuilder_Clear(sbContentType);
    i := i + 1;
  end;

CkEmail_Dispose(email);
CkStringBuilder_Dispose(sbContentType);
            CkEmail_Dispose(attachedEmail);
            CkBinData_Dispose(bdMime);
            CkBinData_Dispose(bd);

end;