Creating a Scheduled Task Through the ITaskService COM Component to Achieve Automatic Startup

Environment

Related Scripts

Implementation Logic

Implementation Principle:

• Use Windows Shell programming to create a scheduled task, which involves knowledge of COM components. The overall program logic can be summarized in three parts: initialization, creating the scheduled task, and deleting the scheduled task.

Initialization

• The purpose of initialization is to obtain the ITaskService and ITaskFolder objects. Creating a scheduled task primarily involves operating on these two pointers. The specific process is:

1.首先初始化COM接口环境，因为我们接下来会使用到COM组件
2.然后，创建 ITaskService 对象，并连接到任务服务上
3.接着，从 ITaskService 对象中获取 ITaskFolder 对象

• Initialization is now complete. Next, directly use the ITaskService and ITaskFolder objects to perform the operations.

Create a Scheduled Task

• Now, examine the specific process for creating the scheduled task:

1.首先，从 ITaskService 对象中创建一个任务定义对象 ITaskDefinition，用来来创建任务
2.接着，就是开始对任务定义对象 ITaskDefinition进行设置：
	(1)设置注册信息，包括设置作者的信息
	(2)设置主体信息，包括登陆类型、运行权限
	(3)设置设置信息，包括设置在使用电池运行时是否停止、在使用电池是是否允许运行、是否允许手动运行、是否设置多个实例
	(4)设置操作信息，包括启动程序，并设置运行程序的路径和参数
	(5)设置触发器信息，包括用户登录时触发
3.最后，使用 ITaskFolder 对象根据任务定义对象 ITaskDefinition的设置，注册任务计划

• This completes creation of the scheduled task. When the configured trigger condition is met, the specified program starts.

Delete a Scheduled Task

• The ITaskFolder object stores information about successfully registered scheduled tasks. We only need to pass the scheduled task's name to it and invoke the DeleteTask interface function to delete the specified scheduled task.

Code Implementation

Initialization for Creating a Scheduled Task

CMyTaskSchedule::CMyTaskSchedule(void)
{
    m_lpITS = NULL;
    m_lpRootFolder = NULL;
    // 初始化COM
    HRESULT hr = ::CoInitialize(NULL);
    if(FAILED(hr))
    {
        ShowError("CoInitialize", hr);
    }
    // 创建一个任务服务（Task Service）实例
    hr = ::CoCreateInstance(CLSID_TaskScheduler,
        NULL,
        CLSCTX_INPROC_SERVER,
        IID_ITaskService,
        (LPVOID *)(&m_lpITS));
    if(FAILED(hr))
    {
        ShowError("CoCreateInstance", hr);
    }
    // 连接到任务服务（Task Service）
    hr = m_lpITS->Connect(_variant_t(), _variant_t(), _variant_t(), _variant_t());
    if(FAILED(hr))
    {
        ShowError("ITaskService::Connect", hr);
    }
    // 获取Root Task Folder的指针，这个指针指向的是新注册的任务
    hr = m_lpITS->GetFolder(_bstr_t("\\"), &m_lpRootFolder);
    if(FAILED(hr))
    {
        ShowError("ITaskService::GetFolder", hr);
    }
}

Create a Scheduled Task

BOOL CMyTaskSchedule::NewTask(char *lpszTaskName, char *lpszProgramPath, char *lpszParameters, char *lpszAuthor)
{
    if(NULL == m_lpRootFolder)
    {
        return FALSE;
    }
    // 如果存在相同的计划任务，则删除
    Delete(lpszTaskName);
    // 创建任务定义对象来创建任务
    ITaskDefinition *pTaskDefinition = NULL;
    HRESULT hr = m_lpITS->NewTask(0, &pTaskDefinition);
    if(FAILED(hr))
    {
        ShowError("ITaskService::NewTask", hr);
        return FALSE;
    }
    /* 设置注册信息 */
    IRegistrationInfo *pRegInfo = NULL;
    CComVariant variantAuthor(NULL);
    variantAuthor = lpszAuthor;
    hr = pTaskDefinition->get_RegistrationInfo(&pRegInfo);
    if(FAILED(hr))
    {
        ShowError("pTaskDefinition::get_RegistrationInfo", hr);
        return FALSE;
    }
    // 设置作者信息
    hr = pRegInfo->put_Author(variantAuthor.bstrVal);
    pRegInfo->Release();
    /* 设置登录类型和运行权限 */
    IPrincipal *pPrincipal = NULL;
    hr = pTaskDefinition->get_Principal(&pPrincipal);
    if(FAILED(hr))
    {
        ShowError("pTaskDefinition::get_Principal", hr);
        return FALSE;
    }
    // 设置登录类型
    hr = pPrincipal->put_LogonType(TASK_LOGON_INTERACTIVE_TOKEN);
    // 设置运行权限
    // 最高权限
    hr = pPrincipal->put_RunLevel(TASK_RUNLEVEL_HIGHEST);  
    pPrincipal->Release();
    /* 设置其他信息 */
    ITaskSettings *pSettting = NULL;
    hr = pTaskDefinition->get_Settings(&pSettting);
    if(FAILED(hr))
    {
        ShowError("pTaskDefinition::get_Settings", hr);
        return FALSE;
    }
    // 设置其他信息
    hr = pSettting->put_StopIfGoingOnBatteries(VARIANT_FALSE);
    hr = pSettting->put_DisallowStartIfOnBatteries(VARIANT_FALSE);
    hr = pSettting->put_AllowDemandStart(VARIANT_TRUE);
    hr = pSettting->put_StartWhenAvailable(VARIANT_FALSE);
    hr = pSettting->put_MultipleInstances(TASK_INSTANCES_PARALLEL);
    pSettting->Release();
    /* 创建执行动作 */
    IActionCollection *pActionCollect = NULL;
    hr = pTaskDefinition->get_Actions(&pActionCollect);
    if(FAILED(hr))
    {
        ShowError("pTaskDefinition::get_Actions", hr);
        return FALSE;
    }
    IAction *pAction = NULL;
    // 创建执行操作
    hr = pActionCollect->Create(TASK_ACTION_EXEC, &pAction);
    pActionCollect->Release();
    /* 设置执行程序路径和参数 */
    CComVariant variantProgramPath(NULL);
    CComVariant variantParameters(NULL);
    IExecAction *pExecAction = NULL;
    hr = pAction->QueryInterface(IID_IExecAction, (PVOID *)(&pExecAction));
    if(FAILED(hr))
    {
        pAction->Release();
        ShowError("IAction::QueryInterface", hr);
        return FALSE;
    }
    pAction->Release();
    // 设置程序路径和参数
    variantProgramPath = lpszProgramPath;
    variantParameters = lpszParameters;
    pExecAction->put_Path(variantProgramPath.bstrVal);
    pExecAction->put_Arguments(variantParameters.bstrVal);
    pExecAction->Release();
    /* 创建触发器，实现用户登陆自启动 */
    ITriggerCollection *pTriggers = NULL;
    hr = pTaskDefinition->get_Triggers(&pTriggers);
    if (FAILED(hr))
    {
        ShowError("pTaskDefinition::get_Triggers", hr);
        return FALSE;
    }
    // 创建触发器
    ITrigger *pTrigger = NULL;
    hr = pTriggers->Create(TASK_TRIGGER_LOGON, &pTrigger);
    if (FAILED(hr))
    {
        ShowError("ITriggerCollection::Create", hr);
        return FALSE;
    }
    /* 注册任务计划  */
    IRegisteredTask *pRegisteredTask = NULL;
    CComVariant variantTaskName(NULL);
    variantTaskName = lpszTaskName;
    hr = m_lpRootFolder->RegisterTaskDefinition(variantTaskName.bstrVal,
        pTaskDefinition,
        TASK_CREATE_OR_UPDATE,
        _variant_t(),
        _variant_t(),
        TASK_LOGON_INTERACTIVE_TOKEN,
        _variant_t(""),
        &pRegisteredTask);
    if(FAILED(hr))
    {
        pTaskDefinition->Release();
        ShowError("ITaskFolder::RegisterTaskDefinition", hr);
        return FALSE;
    }
    pTaskDefinition->Release();
    pRegisteredTask->Release();
    return TRUE;
}

Delete a Scheduled Task

BOOL CMyTaskSchedule::Delete(char *lpszTaskName)
{
    if(NULL == m_lpRootFolder)
    {
        return FALSE;
    }
    CComVariant variantTaskName(NULL);
    variantTaskName = lpszTaskName;
    HRESULT hr = m_lpRootFolder->DeleteTask(variantTaskName.bstrVal, 0);
    if(FAILED(hr))
    {
        return FALSE;
    }
    return TRUE;
}

Test Program

• Invoke the encapsulated functions above in the main function for testing. The main function is:

int _tmain(int argc, _TCHAR* argv[])
{
	CMyTaskSchedule task;
	BOOL bRet = FALSE;

	bRet = task.NewTask("520", "C:\\520.exe", "", "");
	if (FALSE == bRet)
	{
		printf("Create Task Schedule Error!\n");
	}

	printf("Create Task Schedule OK!\n");
	system("pause");

	bRet = task.Delete("520");
	if (FALSE == bRet)
	{
		printf("Delete Task Schedule Error!\n");
	}

	printf("Delete Task Schedule OK!\n");
	system("pause");
	return 0;
}

• Run the program. It reports that the scheduled task was created successfully.

• Open the scheduled task list and confirm that the “520” scheduled task was created successfully.