异步CTP MVC4和工作流程 [英] Async ctp MVC4 and workflows

问题描述

我有低于code它调用的工作流。我想知道如果我可以改变控制器使用异步CTP是异步的。

I have the below code which calls a workflow. I am wondering if I can changed the controller to be asynchronous using the async ctp.

public ActionResult Index()
    {
        var input = new Dictionary<string, object>();
        input["ViewData"] = this.ViewData;
        var userState = "BeginInvoke example";

        var invoker = new WorkflowInvoker(HelloMvcDefinition);

        Task workflowTask = Task.Factory.FromAsync<IDictionary<string, object>>(
            invoker.BeginInvoke(input, WorkflowCompletedCallback, userState),
            invoker.EndInvoke);

        workflowTask.Wait();

        return View();
    }

我已经试过，但我似乎无法得到它的工作：

I have tried this but I cannot seem to get it to work:

public async Task<ActionResult> Index()
    {
        var input = new Dictionary<string, object>();
        input["ViewData"] = this.ViewData;
        var userState = "BeginInvoke example";

        var invoker = new WorkflowInvoker(HelloMvcDefinition);

        Task workflowTask = Task.Factory.FromAsync<IDictionary<string, object>>(
            invoker.BeginInvoke(input, WorkflowCompletedCallback, userState),
            invoker.EndInvoke);

        await workflowTask;

        return View();
    }

不幸的观点似乎并没有工作。什么我做错了任何想法？

Unfortunately the view does not seem to work. Any ideas on what I am doing wrong?

编辑
服用后通知我已经改变了方法，这种

EDIT After taking advice I have changed the method to this

public class HelloController : AsyncController
{
    private static readonly HelloWorkflow HelloMvcDefinition = new HelloWorkflow();

    public Task<ViewResult> Index()
    {
        var input = new Dictionary<string, object>();
        input["ViewData"] = ViewData;
        const string userState = "BeginInvoke example";

        var invoker = new WorkflowInvoker(HelloMvcDefinition);

        return Task.Factory.FromAsync<IDictionary<string, object>>(
            invoker.BeginInvoke(input, WorkflowCompletedCallback, userState),
            invoker.EndInvoke).ContinueWith(t => View());
    }       

    static void WorkflowCompletedCallback(IAsyncResult result)
    {

    }
}

的正常工作，所以这个问题一定要我如何使用异步关键字。

Which works fine so the problem must be how I am using the async keyword.

感谢

推荐答案

我们可以使用TAP模式来调用Windows工作流如下 -
（详细内容在我的博客文章中提到的http://tweetycodingxp.blogspot.com/2013/06/invoke-workflow-wf-using-task-based.html)

We can use the TAP pattern for invoking windows workflow as follows - (Details are mentioned in my blog post http://tweetycodingxp.blogspot.com/2013/06/invoke-workflow-wf-using-task-based.html)

public async Task<ActionResult> Index(string id)
{
    var wfInputArgs = new Dictionary<string, object>
    {
        ...
    };

    var wfOutputArgs = await Task<IDictionary<string, object>>.Factory.StartNew(
        () => WorkflowInvoker.Invoke(new MyWorkflow(), wfInputArgs));
    var result = wfOutputArgs["Output1"] as IEnumerable<Class1>;
    ...
    return View(model);
}

这篇关于异步CTP MVC4和工作流程的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！