Parse winmail.dat (TNEF/MAPI) in Visual C++

In previous section, I introduced how to verify digital signature and decrypt email. In this section, I will introduce how to parse winmail.dat (TNEF stream) in Visual C++.

Introduction

When an Outlook user composes and sends a message using either Rich Text Format or HTML Format, Outlook automagically generates a file, winmail.dat, and attaches it to the end of the email. The winmail.dat contains the rich text body and original attachments. To parse winmail.dat (TNEF stream) file, we should use ParseTNEF method.

Note

Remarks: All of examples in this section are based on first section: A simple Visual C++ project. To compile and run the following example codes successfully, please click here to learn how to create the test project and add reference to your project.

[Visual C++ Example - Parse winmail.dat (TNEF stream)]

The following example codes demonstrate how to parse MAPI winmail.dat.

Note

To get the full sample projects, please refer to Samples section.

#include "stdafx.h"

#include "eagetmailobj.tlh"
using namespace EAGetMailObjLib;

void ParseEmail( LPCTSTR lpszFile )
{
    try
    {
        IMailPtr oMail = NULL;
        oMail.CreateInstance(__uuidof(EAGetMailObjLib::Mail));
        oMail->LicenseCode = _T("TryIt");

        oMail->LoadFile( lpszFile, VARIANT_FALSE );

        if( oMail->IsEncrypted == VARIANT_TRUE )
        {
            // this email is encrypted, we decrypt it by user default certificate.
            // you can also use specified certificate like this
            // ICertificatePtr oCert = NULL;
            // oCert.CreateInstance(__uuidof(EAGetMailObjLib::Certificate));
            // oCert->LoadFromFile(_T("c:\\test.pfx"), _T("pfxpassword"), CRYPT_USER_KEYSET);
            // oMail = oMail->Decrypt( oCert );
            oMail = oMail->Decrypt( NULL );

        }

        if( oMail->IsSigned == VARIANT_TRUE )
        {
            // This email is digital signed.
            ICertificatePtr oCert = oMail->VerifySignature();
            _tprintf( _T("This email contains a valid digital signature.\r\n"));
            // You can add the certificate to your certificate storage like this
            // oCert->AddToStore( CERT_SYSTEM_STORE_CURRENT_USER,
            //      _T("addressbook"));
            // then you can use send the encrypted email back to this sender.
        }

        // Parse email sender
        _tprintf(_T("From: %s\r\n"), (const TCHAR*)oMail->From->Address);

        // Parse to recipient
        _variant_t varry = oMail->To;
        SAFEARRAY *psa = varry.parray;
        long i = 0, LBound = 0, UBound = 0;
        SafeArrayGetLBound( psa, 1, &LBound );
        SafeArrayGetUBound( psa, 1, &UBound );
        for( i = LBound; i <= UBound; i++ )
        {
            _variant_t vt;
            SafeArrayGetElement( psa, &i, &vt );

            IMailAddressPtr pAddr;
            vt.pdispVal->QueryInterface(__uuidof(IMailAddress), (void**)&pAddr);
            _tprintf(_T("To: %s\r\n"), (const TCHAR*)pAddr->Address);
        }

        // Parse CC
        varry = oMail->Cc;
        psa = varry.parray;
        SafeArrayGetLBound( psa, 1, &LBound );
        SafeArrayGetUBound( psa, 1, &UBound );
        for( i = LBound; i <= UBound; i++ )
        {
            _variant_t vt;
            SafeArrayGetElement( psa, &i, &vt );

            IMailAddressPtr pAddr;
            vt.pdispVal->QueryInterface(__uuidof(IMailAddress), (void**)&pAddr);
            _tprintf(_T("Cc: %s\r\n"), (const TCHAR*)pAddr->Address);
        }

        // Parse email subject
        _tprintf(_T("Subject: %s\r\n"), (const TCHAR*)oMail->Subject);

        // Parse email text body
        _tprintf(_T("TextBody: %s\r\n"), (const TCHAR*)oMail->TextBody);

        // Parse email HTML body
        _tprintf(_T("HtmlBody: %s\r\n"), (const TCHAR*)oMail->HtmlBody);

        // Parse attachment
        varry = oMail->Attachments;
        psa = varry.parray;
        SafeArrayGetLBound( psa, 1, &LBound );
        SafeArrayGetUBound( psa, 1, &UBound );
        for( i = LBound; i <= UBound; i++ )
        {
            _variant_t vt;
            SafeArrayGetElement( psa, &i, &vt );

            IAttachmentPtr pAtt;
            vt.pdispVal->QueryInterface(__uuidof(IAttachment), (void**)&pAtt);

            if( _tcsicmp((const TCHAR*)pAtt->Name, _T("winmail.dat")) == 0 )
            {
                // this attachment is in OUTLOOK RTF (TNEF) format, decode it here.
                _variant_t tatts;
                tatts = oMail->ParseTNEF( pAtt->Content, VARIANT_TRUE );

                long XLBound = 0, XUBound = 0;
                SAFEARRAY* tpsa = tatts.parray;
                SafeArrayGetLBound( tpsa, 1, &XLBound );
                SafeArrayGetUBound( tpsa, 1, &XUBound );
                for( long x = XLBound; x <= XUBound; x++ )
                {
                    _variant_t vttAtt;
                    SafeArrayGetElement( tpsa, &x, &vttAtt );
                    IAttachmentPtr ptAtt;
                    vttAtt.pdispVal->QueryInterface( __uuidof(IAttachment), (void**)&ptAtt );
                    _tprintf(_T("winmail.dat: %s\r\n"), (const TCHAR*)ptAtt->Name);
                }
                continue;
            }

            _tprintf(_T("Attachment: %s\r\n"), (const TCHAR*)pAtt->Name);
        }

    }
    catch( _com_error &ep )
    {
        _tprintf(_T("Error: %s\r\n"), (const TCHAR*)ep.Description());
    }
}

int _tmain(int argc, _TCHAR* argv[])
{
    const int MailServerPop3 = 0;
    const int MailServerImap4 = 1;

    // Initialize COM environment
    ::CoInitialize( NULL );

    // Create a folder named "inbox" under current exe file directory
    // to save the emails retrieved.
    TCHAR szPath[MAX_PATH+1];
    memset( szPath, 0, sizeof(szPath));
    ::GetModuleFileName( NULL, szPath,  MAX_PATH );

    // Change file name to current full path
    LPCTSTR psz = _tcsrchr( szPath, _T('\\'));
    if( psz != NULL )
    {
        szPath[psz-szPath] = _T('\0');
    }
    TCHAR szMailBox[MAX_PATH+1];
    memset( szMailBox, 0, sizeof(szMailBox));
    wsprintf( szMailBox, _T("%s\\inbox"), szPath );

    // Create a folder to store emails
    ::CreateDirectory( szMailBox, NULL );

    try
    {
        IToolsPtr oTools = NULL;
        oTools.CreateInstance(__uuidof(EAGetMailObjLib::Tools));
        TCHAR szFind[MAX_PATH+1];
        memset( szFind, 0, sizeof(szFind));
        wsprintf( szFind, _T("%s\\*.eml"), szMailBox );

        // Get all *.eml files in specified folder and parse it one by one.
        _variant_t files = oTools->GetFiles( szFind );
        SAFEARRAY *psa = files.parray;
        long i = 0, LBound = 0, UBound = 0;
        SafeArrayGetLBound( psa, 1, &LBound );
        SafeArrayGetUBound( psa, 1, &UBound );
        for( i = LBound; i <= UBound; i++ )
        {
            _variant_t vt;
            SafeArrayGetElement( psa, &i, &vt );

            ParseEmail(_bstr_t(vt.bstrVal));
        }
    }
    catch( _com_error &ep )
    {
        _tprintf( _T("Error: %s"), (const TCHAR*)ep.Description());
    }

    return 0;
}

Parse TNEF (winmail.dat) by DecodeTNEF method

In EAGetMail 4.5, a new method named DecodeTNEF is introduced. It is easier to parse TNEF attachment. Please have a look at the following example codes:

#include "stdafx.h"

#include "eagetmailobj.tlh"
using namespace EAGetMailObjLib;

void ParseEmail( LPCTSTR lpszFile )
{
    try
    {
        IMailPtr oMail = NULL;
        oMail.CreateInstance(__uuidof(EAGetMailObjLib::Mail));
        oMail->LicenseCode = _T("TryIt");

        oMail->LoadFile( lpszFile, VARIANT_FALSE );

        if( oMail->IsEncrypted == VARIANT_TRUE )
        {
            // this email is encrypted, we decrypt it by user default certificate.
            // you can also use specified certificate like this
            // ICertificatePtr oCert = NULL;
            // oCert.CreateInstance(__uuidof(EAGetMailObjLib::Certificate));
            // oCert->LoadFromFile(_T("c:\\test.pfx"), _T("pfxpassword"), CRYPT_USER_KEYSET);
            // oMail = oMail->Decrypt( oCert );
            oMail = oMail->Decrypt( NULL );

        }

        if( oMail->IsSigned == VARIANT_TRUE )
        {
            // This email is digital signed.
            ICertificatePtr oCert = oMail->VerifySignature();
            _tprintf( _T("This email contains a valid digital signature.\r\n"));
            // You can add the certificate to your certificate storage like this
            // oCert->AddToStore( CERT_SYSTEM_STORE_CURRENT_USER,
            //      _T("addressbook"));
            // then you can use send the encrypted email back to this sender.
        }

        // Decode winmail.dat (TNEF) automatically
        oMail->DecodeTNEF();

        // Parse email sender
        _tprintf(_T("From: %s\r\n"), (const TCHAR*)oMail->From->Address);

        // Parse to recipient
        _variant_t varry = oMail->To;
        SAFEARRAY *psa = varry.parray;
        long i = 0, LBound = 0, UBound = 0;
        SafeArrayGetLBound( psa, 1, &LBound );
        SafeArrayGetUBound( psa, 1, &UBound );
        for( i = LBound; i <= UBound; i++ )
        {
            _variant_t vt;
            SafeArrayGetElement( psa, &i, &vt );

            IMailAddressPtr pAddr;
            vt.pdispVal->QueryInterface(__uuidof(IMailAddress), (void**)&pAddr);
            _tprintf(_T("To: %s\r\n"), (const TCHAR*)pAddr->Address);
        }

        // Parse CC
        varry = oMail->Cc;
        psa = varry.parray;
        SafeArrayGetLBound( psa, 1, &LBound );
        SafeArrayGetUBound( psa, 1, &UBound );
        for( i = LBound; i <= UBound; i++ )
        {
            _variant_t vt;
            SafeArrayGetElement( psa, &i, &vt );

            IMailAddressPtr pAddr;
            vt.pdispVal->QueryInterface(__uuidof(IMailAddress), (void**)&pAddr);
            _tprintf(_T("Cc: %s\r\n"), (const TCHAR*)pAddr->Address);
        }

        // Parse email subject
        _tprintf(_T("Subject: %s\r\n"), (const TCHAR*)oMail->Subject);

        // Parse email text body
        _tprintf(_T("TextBody: %s\r\n"), (const TCHAR*)oMail->TextBody);

        // Parse email HTML body
        _tprintf(_T("HtmlBody: %s\r\n"), (const TCHAR*)oMail->HtmlBody);

        // Parse attachment
        varry = oMail->Attachments;
        psa = varry.parray;
        SafeArrayGetLBound( psa, 1, &LBound );
        SafeArrayGetUBound( psa, 1, &UBound );
        for( i = LBound; i <= UBound; i++ )
        {
            _variant_t vt;
            SafeArrayGetElement( psa, &i, &vt );

            IAttachmentPtr pAtt;
            vt.pdispVal->QueryInterface(__uuidof(IAttachment), (void**)&pAtt);

            _tprintf(_T("Attachment: %s\r\n"), (const TCHAR*)pAtt->Name);
        }

    }
    catch( _com_error &ep )
    {
        _tprintf(_T("Error: %s\r\n"), (const TCHAR*)ep.Description());
    }
}

int _tmain(int argc, _TCHAR* argv[])
{
    const int MailServerPop3 = 0;
    const int MailServerImap4 = 1;

    // Initialize COM environment
    ::CoInitialize( NULL );

    // Create a folder named "inbox" under current exe file directory
    // to save the emails retrieved.
    TCHAR szPath[MAX_PATH+1];
    memset( szPath, 0, sizeof(szPath));
    ::GetModuleFileName( NULL, szPath,  MAX_PATH );

    // Change file name to current full path
    LPCTSTR psz = _tcsrchr( szPath, _T('\\'));
    if( psz != NULL )
    {
        szPath[psz-szPath] = _T('\0');
    }
    TCHAR szMailBox[MAX_PATH+1];
    memset( szMailBox, 0, sizeof(szMailBox));
    wsprintf( szMailBox, _T("%s\\inbox"), szPath );

    // Create a folder to store emails
    ::CreateDirectory( szMailBox, NULL );

    try
    {
        IToolsPtr oTools = NULL;
        oTools.CreateInstance(__uuidof(EAGetMailObjLib::Tools));
        TCHAR szFind[MAX_PATH+1];
        memset( szFind, 0, sizeof(szFind));
        wsprintf( szFind, _T("%s\\*.eml"), szMailBox );

        // Get all *.eml files in specified folder and parse it one by one.
        _variant_t files = oTools->GetFiles( szFind );
        SAFEARRAY *psa = files.parray;
        long i = 0, LBound = 0, UBound = 0;
        SafeArrayGetLBound( psa, 1, &LBound );
        SafeArrayGetUBound( psa, 1, &UBound );
        for( i = LBound; i <= UBound; i++ )
        {
            _variant_t vt;
            SafeArrayGetElement( psa, &i, &vt );

            ParseEmail(_bstr_t(vt.bstrVal));
        }
    }
    catch( _com_error &ep )
    {
        _tprintf( _T("Error: %s"), (const TCHAR*)ep.Description());
    }

    return 0;
}

Next Section

At next section I will introduce how to convert email to HTML page and display it in Web browser.

Appendix

Comments

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