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Beispiel-ICE in C++

Dieser Beispielcode stammt aus einer benutzerdefinierten ICE-Aktion (ICE01). Er überprüft, ob der ICE-Mechanismus funktioniert, indem die Uhrzeit angezeigt wird. Der ICE gibt eine Meldung mit der Uhrzeit aus, zu der das Installationsprogramm den ICE aufgerufen hat. Dieser ICE sollte niemals einen Fehler zurückgeben.

// 
// test of external database access
#include <windows.h>
#include <stdio.h>
#include <tchar.h>
#include <strsafe.h>
#include <MsiQuery.h>
#pragma comment(lib, "msi.lib")

///////////////////////////////////////////////////////////
// ICE01 - simple ICE that does not test anything
UINT __stdcall ICE01(MSIHANDLE hInstall)
{
    // setup the record to describe owner and date created
    PMSIHANDLE hRecCreated = ::MsiCreateRecord(1);
    ::MsiRecordSetString(hRecCreated, 0, TEXT("ICE01\t3\tCreated 04/29/1998 by <insert author's name here>"));

    // post the owner message
    ::MsiProcessMessage(hInstall, INSTALLMESSAGE(INSTALLMESSAGE_USER), hRecCreated); 
    // setup the record to describe the last time the ICE was modified
    ::MsiRecordSetString(hRecCreated, 0, TEXT("ICE01\t3\tLast modified 05/06/1998 by <insert author's name here>"));

    // post the last modification message
    ::MsiProcessMessage(hInstall, INSTALLMESSAGE(INSTALLMESSAGE_USER), hRecCreated);

    // setup the record to describe what the ICE evaluates
    ::MsiRecordSetString(hRecCreated, 0, TEXT("ICE01\t3\tSimple ICE illustrating the ICE concept"));

    // post the description of evaluation message
    ::MsiProcessMessage(hInstall, INSTALLMESSAGE(INSTALLMESSAGE_USER), hRecCreated);
    // time value to be sent on
    TCHAR szValue[200];
    DWORD cchValue = sizeof(szValue)/sizeof(TCHAR);

    // try to get the time of this call
    if (MsiGetProperty(hInstall, TEXT("Time"), szValue, &cchValue) != ERROR_SUCCESS)
        StringCchCopy(szValue,  sizeof("(none)")/sizeof(TCHAR)+1, TEXT("none"));// no time available

    // setup the record to be sent as a message
    PMSIHANDLE hRecTime = ::MsiCreateRecord(2);
    ::MsiRecordSetString(hRecTime, 0, TEXT("ICE01\t3\tCalled at [1]."));
    ::MsiRecordSetString(hRecTime, 1, szValue);

    // send the time
    ::MsiProcessMessage(hInstall, INSTALLMESSAGE(INSTALLMESSAGE_USER), hRecTime);

    return ERROR_SUCCESS; // allows other ICEs will continue
}