WorkflowApplication 类

定义

public ref class WorkflowApplication sealed : System::Activities::Hosting::WorkflowInstance

public sealed class WorkflowApplication : System.Activities.Hosting.WorkflowInstance

type WorkflowApplication = class
    inherit WorkflowInstance

Public NotInheritable Class WorkflowApplication
Inherits WorkflowInstance

继承

Object

WorkflowInstance

WorkflowApplication

示例

以下示例使用 WorkflowApplication 承载工作流。 WorkflowApplication使用指定的工作流定义构造实例，处理所需的工作流生命周期事件，并通过调用Run调用调用工作流。 工作流完成后，以下输出会显示到控制台。

Starting the workflow.
Workflow 593976e8-558d-4989-94d6-50a14b34fd7b Idle.
Ending the workflow.
Workflow 593976e8-558d-4989-94d6-50a14b34fd7b Completed
Workflow 593976e8-558d-4989-94d6-50a14b34fd7b Unloaded.

Activity wf = new Sequence
{
    Activities =
     {
         new WriteLine
         {
             Text = "Starting the workflow."
         },
         new Delay
         {
             Duration = TimeSpan.FromSeconds(5)
         },
         new WriteLine
         {
             Text = "Ending the workflow."
         }
     }
};

// Create a WorkflowApplication instance.
WorkflowApplication wfApp = new WorkflowApplication(wf);

// Subscribe to any desired workflow lifecycle events.
wfApp.Completed = delegate(WorkflowApplicationCompletedEventArgs e)
{
    if (e.CompletionState == ActivityInstanceState.Faulted)
    {
        Console.WriteLine("Workflow {0} Terminated.", e.InstanceId);
        Console.WriteLine("Exception: {0}\n{1}",
            e.TerminationException.GetType().FullName,
            e.TerminationException.Message);
    }
    else if (e.CompletionState == ActivityInstanceState.Canceled)
    {
        Console.WriteLine("Workflow {0} Canceled.", e.InstanceId);
    }
    else
    {
        Console.WriteLine("Workflow {0} Completed.", e.InstanceId);

        // Outputs can be retrieved from the Outputs dictionary,
        // keyed by argument name.
        // Console.WriteLine("The winner is {0}.", e.Outputs["Winner"]);
    }
};

wfApp.Aborted = delegate(WorkflowApplicationAbortedEventArgs e)
{
    // Display the exception that caused the workflow
    // to abort.
    Console.WriteLine("Workflow {0} Aborted.", e.InstanceId);
    Console.WriteLine("Exception: {0}\n{1}",
        e.Reason.GetType().FullName,
        e.Reason.Message);
};

wfApp.Idle = delegate(WorkflowApplicationIdleEventArgs e)
{
    // Perform any processing that should occur
    // when a workflow goes idle. If the workflow can persist,
    // both Idle and PersistableIdle are called in that order.
    Console.WriteLine("Workflow {0} Idle.", e.InstanceId);
};

wfApp.PersistableIdle = delegate(WorkflowApplicationIdleEventArgs e)
{
    // Instruct the runtime to persist and unload the workflow
    return PersistableIdleAction.Unload;
};

wfApp.Unloaded = delegate(WorkflowApplicationEventArgs e)
{
    Console.WriteLine("Workflow {0} Unloaded.", e.InstanceId);
};

wfApp.OnUnhandledException = delegate(WorkflowApplicationUnhandledExceptionEventArgs e)
{
    // Display the unhandled exception.
    Console.WriteLine("OnUnhandledException in Workflow {0}\n{1}",
        e.InstanceId, e.UnhandledException.Message);

    Console.WriteLine("ExceptionSource: {0} - {1}",
        e.ExceptionSource.DisplayName, e.ExceptionSourceInstanceId);

    // Instruct the runtime to terminate the workflow.
    // Other choices are Abort and Cancel
    return UnhandledExceptionAction.Terminate;
};

// Run the workflow.
wfApp.Run();

注解

该 WorkflowApplication 类为单个工作流实例提供主机。 它是由工作流运行时管理的实际工作流实例的代理。 WorkflowApplication用户可以通过对对象调用适当的方法WorkflowApplication，指示工作流运行时对工作流实例执行操作。 如果请求的操作无效，则会引发异常。

使用 WorkflowApplication 可以执行以下任务：

1. 创建新的工作流实例，或从实例存储加载工作流实例。

2. 提供工作流实例中的活动要使用的扩展。

3. 控制工作流实例的执行。

4. 恢复由工作流实例中的活动创建的书签。

5. 保留或卸载工作流实例。

6. 收到工作流实例生命周期事件的通知。