Exemplo de gatilho de tempo (C++)

Este exemplo do C++ mostra como criar uma tarefa agendada para executar o Bloco de Notas em um momento especificado. A tarefa contém um gatilho baseado em tempo que especifica um limite inicial e um limite final para a tarefa. A tarefa também contém uma ação que especifica a tarefa para executar o Bloco de Notas. A tarefa é registrada usando um tipo de logon interativo, o que significa que a tarefa é executada no contexto de segurança do usuário que executa o aplicativo. A tarefa também contém configurações ociosas, que especifica como o Agendador de Tarefas executa tarefas quando o computador está em uma condição ociosa.

O procedimento a seguir descreve como agendar uma tarefa para iniciar um executável em um determinado momento.

Para agendar o Bloco de Notas para iniciar em um momento específico

  1. Inicialize COM e defina a segurança COM geral.

  2. Crie o objeto ITaskService .

    Esse objeto permite que você crie tarefas em uma pasta especificada.

  3. Obtenha uma pasta de tarefa na qual criar uma tarefa.

    Use o método ITaskService::GetFolder para obter a pasta e o método ITaskService::NewTask para criar o objeto ITaskDefinition .

  4. Defina informações sobre a tarefa usando o objeto ITaskDefinition , como as informações de registro da tarefa.

    Use a propriedade RegistrationInfo de ITaskDefinition e outras propriedades da interface ITaskDefinition para definir as informações da tarefa.

  5. Crie um gatilho baseado em tempo usando a propriedade Triggers de ITaskDefinition para acessar o ITriggerCollection para a tarefa.

    Use o método ITriggerCollection::Create (especificando o tipo de gatilho que você deseja criar) para criar um gatilho baseado em tempo. Isso permite que você defina o limite inicial e o limite final do gatilho para que as ações da tarefa sejam agendadas para serem executadas em um momento especificado.

  6. Crie uma ação para a tarefa a ser executada usando a propriedade Actions de ITaskDefinition para acessar a interface IActionCollection para a tarefa.

    Use o método IActionCollection::Create para especificar o tipo de ação que você deseja criar. Este exemplo usa um objeto IExecAction , que representa uma ação que executa uma operação de linha de comando.

  7. Registre a tarefa usando o método ITaskFolder::RegisterTaskDefinition .

O exemplo do C++ a seguir mostra como agendar uma tarefa para executar o Bloco de Notas um minuto após o registro da tarefa.

/********************************************************************
 This sample schedules a task to start notepad.exe 1 minute from the
 time the task is registered. 
********************************************************************/

#define _WIN32_DCOM

#include <windows.h>
#include <iostream>
#include <stdio.h>
#include <comdef.h>
#include <wincred.h>
//  Include the task header file.
#include <taskschd.h>
#pragma comment(lib, "taskschd.lib")
#pragma comment(lib, "comsupp.lib")
#pragma comment(lib, "credui.lib")

using namespace std;


int __cdecl wmain()
{
    //  ------------------------------------------------------
    //  Initialize COM.
    HRESULT hr = CoInitializeEx(NULL, COINIT_MULTITHREADED);
    if( FAILED(hr) )
    {
        printf("\nCoInitializeEx failed: %x", hr );
        return 1;
    }

    //  Set general COM security levels.
    hr = CoInitializeSecurity(
        NULL,
        -1,
        NULL,
        NULL,
        RPC_C_AUTHN_LEVEL_PKT_PRIVACY,
        RPC_C_IMP_LEVEL_IMPERSONATE,
        NULL,
        0,
        NULL);

    if( FAILED(hr) )
    {
        printf("\nCoInitializeSecurity failed: %x", hr );
        CoUninitialize();
        return 1;
    }

    //  ------------------------------------------------------
    //  Create a name for the task.
    LPCWSTR wszTaskName = L"Time Trigger Test Task";

    //  Get the windows directory and set the path to notepad.exe.
    wstring wstrExecutablePath = _wgetenv( L"WINDIR");
    wstrExecutablePath += L"\\SYSTEM32\\NOTEPAD.EXE";


    //  ------------------------------------------------------
    //  Create an instance of the Task Service. 
    ITaskService *pService = NULL;
    hr = CoCreateInstance( CLSID_TaskScheduler,
                           NULL,
                           CLSCTX_INPROC_SERVER,
                           IID_ITaskService,
                           (void**)&pService );  
    if (FAILED(hr))
    {
        printf("Failed to create an instance of ITaskService: %x", hr);
        CoUninitialize();
        return 1;
    }
        
    //  Connect to the task service.
    hr = pService->Connect(_variant_t(), _variant_t(),
        _variant_t(), _variant_t());
    if( FAILED(hr) )
    {
        printf("ITaskService::Connect failed: %x", hr );
        pService->Release();
        CoUninitialize();
        return 1;
    }

    //  ------------------------------------------------------
    //  Get the pointer to the root task folder.  This folder will hold the
    //  new task that is registered.
    ITaskFolder *pRootFolder = NULL;
    hr = pService->GetFolder( _bstr_t( L"\\") , &pRootFolder );
    if( FAILED(hr) )
    {
        printf("Cannot get Root folder pointer: %x", hr );
        pService->Release();
        CoUninitialize();
        return 1;
    }
    
    //  If the same task exists, remove it.
    pRootFolder->DeleteTask( _bstr_t( wszTaskName), 0  );
    
    //  Create the task definition object to create the task.
    ITaskDefinition *pTask = NULL;
    hr = pService->NewTask( 0, &pTask );

    pService->Release();  // COM clean up.  Pointer is no longer used.
    if (FAILED(hr))
    {
        printf("Failed to CoCreate an instance of the TaskService class: %x", hr);
        pRootFolder->Release();
        CoUninitialize();
        return 1;
    }
        
    //  ------------------------------------------------------
    //  Get the registration info for setting the identification.
    IRegistrationInfo *pRegInfo= NULL;
    hr = pTask->get_RegistrationInfo( &pRegInfo );
    if( FAILED(hr) )
    {
        printf("\nCannot get identification pointer: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }
    
    hr = pRegInfo->put_Author( L"Author Name" );    
    pRegInfo->Release();  
    if( FAILED(hr) )
    {
        printf("\nCannot put identification info: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }

    //  ------------------------------------------------------
    //  Create the principal for the task - these credentials
    //  are overwritten with the credentials passed to RegisterTaskDefinition
    IPrincipal *pPrincipal = NULL;
    hr = pTask->get_Principal( &pPrincipal );
    if( FAILED(hr) )
    {
        printf("\nCannot get principal pointer: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }
    
    //  Set up principal logon type to interactive logon
    hr = pPrincipal->put_LogonType( TASK_LOGON_INTERACTIVE_TOKEN );
    pPrincipal->Release();
    if( FAILED(hr) )
    {
        printf("\nCannot put principal info: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }  

    //  ------------------------------------------------------
    //  Create the settings for the task
    ITaskSettings *pSettings = NULL;
    hr = pTask->get_Settings( &pSettings );
    if( FAILED(hr) )
    {
        printf("\nCannot get settings pointer: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }
    
    //  Set setting values for the task.  
    hr = pSettings->put_StartWhenAvailable(VARIANT_TRUE);
    pSettings->Release();
    if( FAILED(hr) )
    {
        printf("\nCannot put setting information: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }

    // Set the idle settings for the task.
    IIdleSettings *pIdleSettings = NULL;
    hr = pSettings->get_IdleSettings( &pIdleSettings );
    if( FAILED(hr) )
    {
        printf("\nCannot get idle setting information: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }

    hr = pIdleSettings->put_WaitTimeout(L"PT5M");
    pIdleSettings->Release();
    if( FAILED(hr) )
    {
        printf("\nCannot put idle setting information: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }
    

    //  ------------------------------------------------------
    //  Get the trigger collection to insert the time trigger.
    ITriggerCollection *pTriggerCollection = NULL;
    hr = pTask->get_Triggers( &pTriggerCollection );
    if( FAILED(hr) )
    {
        printf("\nCannot get trigger collection: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }

    //  Add the time trigger to the task.
    ITrigger *pTrigger = NULL;    
    hr = pTriggerCollection->Create( TASK_TRIGGER_TIME, &pTrigger );     
    pTriggerCollection->Release();
    if( FAILED(hr) )
    {
        printf("\nCannot create trigger: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }

    ITimeTrigger *pTimeTrigger = NULL;
    hr = pTrigger->QueryInterface( 
        IID_ITimeTrigger, (void**) &pTimeTrigger );
    pTrigger->Release();
    if( FAILED(hr) )
    {
        printf("\nQueryInterface call failed for ITimeTrigger: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }

    hr = pTimeTrigger->put_Id( _bstr_t( L"Trigger1" ) );
    if( FAILED(hr) )
        printf("\nCannot put trigger ID: %x", hr);

    hr = pTimeTrigger->put_EndBoundary( _bstr_t(L"2015-05-02T08:00:00") );
    if( FAILED(hr) )
        printf("\nCannot put end boundary on trigger: %x", hr);

    //  Set the task to start at a certain time. The time 
    //  format should be YYYY-MM-DDTHH:MM:SS(+-)(timezone).
    //  For example, the start boundary below
    //  is January 1st 2005 at 12:05
    hr = pTimeTrigger->put_StartBoundary( _bstr_t(L"2005-01-01T12:05:00") );
    pTimeTrigger->Release();    
    if( FAILED(hr) )
    {
        printf("\nCannot add start boundary to trigger: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }
    

    //  ------------------------------------------------------
    //  Add an action to the task. This task will execute notepad.exe.     
    IActionCollection *pActionCollection = NULL;

    //  Get the task action collection pointer.
    hr = pTask->get_Actions( &pActionCollection );
    if( FAILED(hr) )
    {
        printf("\nCannot get Task collection pointer: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }
    
    //  Create the action, specifying that it is an executable action.
    IAction *pAction = NULL;
    hr = pActionCollection->Create( TASK_ACTION_EXEC, &pAction );
    pActionCollection->Release();
    if( FAILED(hr) )
    {
        printf("\nCannot create the action: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }

    IExecAction *pExecAction = NULL;
    //  QI for the executable task pointer.
    hr = pAction->QueryInterface( 
        IID_IExecAction, (void**) &pExecAction );
    pAction->Release();
    if( FAILED(hr) )
    {
        printf("\nQueryInterface call failed for IExecAction: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }

    //  Set the path of the executable to notepad.exe.
    hr = pExecAction->put_Path( _bstr_t( wstrExecutablePath.c_str() ) );
    pExecAction->Release();
    if( FAILED(hr) )
    {
        printf("\nCannot put action path: %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }  
    
    //  ------------------------------------------------------
    //  Save the task in the root folder.
    IRegisteredTask *pRegisteredTask = NULL;
    hr = pRootFolder->RegisterTaskDefinition(
            _bstr_t( wszTaskName ),
            pTask,
            TASK_CREATE_OR_UPDATE, 
            _variant_t(), 
            _variant_t(), 
            TASK_LOGON_INTERACTIVE_TOKEN,
            _variant_t(L""),
            &pRegisteredTask);
    if( FAILED(hr) )
    {
        printf("\nError saving the Task : %x", hr );
        pRootFolder->Release();
        pTask->Release();
        CoUninitialize();
        return 1;
    }
    
    printf("\n Success! Task successfully registered. " );

    //  Clean up.
    pRootFolder->Release();
    pTask->Release();
    pRegisteredTask->Release();
    CoUninitialize();
    return 0;
}

Usando o Agendador de Tarefas