这通常是长时间运行的工作流的最小示例,它等待控制台上的用户输入。 (此代码永远不会执行,把它作为唯一的一个例子)
/// Activity that waits on bookmark for
/// someone to send it some text
///
public sealed class ReadLine: NativeActivity<string>
{
[RequiredArgument]
public InArgument<string> BookmarkName { get; set; }
protected override bool CanInduceIdle
{
get
{
return true;
}
}
protected override void Execute(NativeActivityContext context)
{
context.CreateBookmark(
BookmarkName.Get(context),
new BookmarkCallback(OnReadComplete));
}
void OnReadComplete(NativeActivityContext context, Bookmark bookmark, object state)
{
context.SetValue(base.Result, state as string);
}
}
/// Program that uses ReadLine activity's bookmark to persist
/// workflow and waits for user input to resume it
///
public class Program
{
static InstanceStore InstanceStore;
static Activity Activity = GetExampleActivity();
static AutoResetEvent unloadEvent = new AutoResetEvent(false);
static Guid WfId;
static WorkflowApplication WfApp;
const string READ_LINE_BOOKMARK = "ReadLineBookMark";
static void Main()
{
CreateInstanceStore();
CreateWorkflowApp();
// Start workflow application and wait for input
StartAndUnload();
//Get user input and send it to ReadLine bookmark reviving workflow
GetInputAndComplete();
}
static void StartAndUnload()
{
WfApp.Run();
WfId = app.Id;
// !! Workflow will go idle on bookmark, no need to call Unload()
unloadEvent.WaitOne();
}
static void GetInputAndComplete()
{
var input = Console.ReadLine();
// We've the text input, let's resume this thing
WfApp.Load(WfId);
WfApp.ResumeBookmark(READ_LINE_BOOKMARK, input);
unloadEvent.WaitOne();
}
static void CreateInstanceStore()
{
InstanceStore = new SqlWorkflowInstanceStore("connection string");
var handle = InstanceStore.CreateInstanceHandle();
var view = InstanceStore.Execute(
handle,
new CreateWorkflowOwnerCommand(),
TimeSpan.FromSeconds(5));
handle.Free();
InstanceStore.DefaultInstanceOwner = view.InstanceOwner;
}
static void CreateWorkflowApp()
{
WfApp = new WorkflowApplication(Activity)
{
InstanceStore = InstanceStore,
};
WfApp.PersistableIdle = (e) => { return PersistableIdleAction.Unload; }
WfApp.Unloaded = (e) =>
{
Console.WriteLine("WF App Unloaded\n");
unloadEvent.Set();
};
WfApp.Completed = (e) =>
{
Console.WriteLine("\nWF App Ended: {0}.", e.CompletionState);
};
}
static Activity GetExampleActivity()
{
var response = new Variable<string>();
return return new Sequence()
{
Variables = { response },
Activities =
{
new WriteLine()
{
Text = new InArgument<string>("Type some word:")
},
new ReadLine()
{
BookmarkName = READ_LINE_BOOKMARK,
Result = new OutArgument<string>(response)
},
new WriteLine()
{
Text = new InArgument<string>((context) => "You've typed: " + response.Get(context))
}
}
};
}
话虽这么说,请考虑使用IIS和AppFabric的,你会不会后悔。 AppFabric有六次点击,在WF中实现了两个必须要做的痛苦事情:持久性和监控。如果您选择此路径,您不会永远不需要编写代码。
将您的工作流程部署为WCF应用程序,并将其作为任何其他WCF合同进行调用。你有OperationContracts这是接收活动(那些谁等待并坚持,如果它需要太长时间)和相应的发送活动(谁返回给客户端)。你甚至有他们之间的相关性的概念。AppFabric负责恢复工作流,只是传递一个先前初始化的相关句柄。
AppFabric为您提供了一个配置用户界面来配置持久性存储,监控和其他选项,如闲置和/或保持之前的时间。
您可以直观的有功/无/暂停工作流程,监测数据,等等,等等
有没有什么不能承载这些工作流程为通过IIS服务的一个原因? –
Mike: 谢谢。你会怎么看?我会得到什么好处?这可能是一种可能性,我不明白为什么,但另一方面,我也不明白为什么。 :-) –