Microsoft KB Archive/252649

Knowledge Base

How To Open a MAPI IMessage Interface with CDO Entry ID

Article ID: 252649

Article Last Modified on 8/25/2005

---

APPLIES TO

• Microsoft Messaging Application Programming Interface
• Microsoft Collaboration Data Objects 1.2
• Microsoft Collaboration Data Objects 1.21

---

This article was previously published under Q252649

SUMMARY

When you work with CDO using Microsoft Visual C++, it may sometimes be necessary to switch over to MAPI. The code in the "More Information" section shows how to take a message in CDO and open that same message in MAPI.

MORE INFORMATION

//This code assumes that CDO has been imported with the following statement
//#import "cdo.dll" no_namespace
//and that we have a MAPI session opened with the same profile as the CDO session.
HRESULT OpenMAPIMessageFromCDOMessage(
    LPMAPISESSION lpMAPISession,
    MessagePtr pCDOMessage,
    LPMESSAGE* lppMessage)
{
    HRESULT hRes = S_OK;
    int cbSEID;
    LPENTRYID pbSEID;
    int cbEID;
    LPENTRYID pbEID;

    //Find CDO's StoreID
    bstr_t szStoreEID = pCDOMessage->StoreID;

    //Convert the StoreID to a byte array for OpenMsgStore
    cbSEID = strlen(szStoreEID)/2;
    hRes = MAPIAllocateBuffer(cbSEID, (void **)&pbSEID);
    FBinFromHex(szStoreEID, (LPBYTE)pbSEID);

    hRes = lpMAPISession->OpenMsgStore(
        0,
        cbSEID,
        pbSEID,
        0,
        MAPI_BEST_ACCESS,
        &lpMDB);
    MAPIFreeBuffer(pbSEID);
    if (FAILED(hRes)) return hRes;

    _variant_t lClass = pMessage->Class;

    //Find the CDO message's Entry ID
    bstr_t szEID
    if ((LONG) lClass == 26)//that is, we have an appointment item
    {
        //CDO tacks on 80 extra bytes to appointment item IDs. Skip them.
        szEID = ((char *)(bstr_t)pMessage->ID)+80;
    }
    else 
    {
        szEID = pCDOMessage->ID;
    }

    //Convert the ID to a byte array for OpenMsgStore
    cbEID = strlen(szEID)/2;
    hRes = MAPIAllocateBuffer(cbEID, (void **)&pbEID);
    FBinFromHex(szEID, (LPBYTE) pbEID);

    hRes = lpMDB->OpenEntry(
        cbEID,
        pbEID,
        0,
        MAPI_BEST_ACCESS,
        &lpObjType,
        (LPUNKNOWN *) lppMessage);
    MAPIFreeBuffer(pbEID);
    if (FAILED(hRes)) return hRes;

    if (lpMDB) lpMDB->Release();
    return hRes;
}
                

Keywords: kbhowto kbmsg KB252649

---

Send feedback to Microsoft

© Microsoft Corporation. All rights reserved.