Task.Run 参数在 ASP MVC 中不起作用，但在没有传入参数的情况下工作

Question

我有下面的代码，它在方法没有参数时有效，但在我传入参数时无效。我最初认为，当 IIS 中的上下文丢失时，参数也会丢失，所以我做了一个深拷贝，同样的事情仍然发生。我也尝试记录错误或消息，但同样的事情 - 它从不调用方法来完成任务。初始日志消息写入成功，但不是我想添加的方法中的日志消息发生在 asp mvc 项目中。我已经在这个问题上待了 2 天，在 stackoverflow 和谷歌上都没有解决方案。我添加了线程睡眠以使后台线程可能启动，但它不起作用。 currentcontroller 继承自 basecontroller 类。记录器使用 log4net。日志记录有效，我看到数据库中的条目。添加了 thread.sleep 以查看它是否通过使父线程等待后台线程启动来解决问题。有什么想法吗？

public class MainController : BaseController
{
    [HttpPost]
    public JsonResult ProcessSynchronization(int sourceId, string[] cities)
    {
        var ret = false;
        try
        {              

            if (sourceId == 1)
            { 
                var cityDeep = (string[])cities.Clone();
                Logger.Info("ABout to start BeginSynchronization ..");

                Task.Factory.StartNew(() =>
                {
                    Logger.Info("ABout to start BeginSynchronization enter..");

                    BeginSynchronization(cityDeep);
                });


                Thread.Sleep(5000);
                ret = true;
            }

        }
        catch (Exception ex)
        {
            Logger.Error(LogUtility.BuildExceptionMessage(ex), ex);
            return Json(new { result = ret, responseText = "Customer could not be activated." });
        }
        return Json(new { result = ret, responseText = "Synchronization started." });
    }

    private void BeginSynchronization (string[] cities)
    {
        Logger.Info("BeginSynchronization entry processing..");

    }
}

public class BaseController : Controller
{
    /// <summary>
    /// Get logger
    /// </summary>
    protected ILog Logger
    {
        get { return LogManager.GetLogger(GetType()); }
    }
}

Answer 1

尝试用async/await关键字修改你的方法。

public async JsonResult ProcessSynchronization(int sourceId, string[] cities)
{
    var ret = false;
    try
    {              

        if (sourceId == 1)
        { 
            var cityDeep = (string[])cities.Clone();
            Logger.Info("ABout to start BeginSynchronization ..");

            await Task.Factory.StartNew(() =>
            {
                Logger.Info("ABout to start BeginSynchronization enter..");

                BeginSynchronization(cityDeep);
            });


            ret = true;
        }

    }
    catch (Exception ex)
    {
        Logger.Error(LogUtility.BuildExceptionMessage(ex), ex);
        return Json(new { result = ret, responseText = "Customer could not be activated." });
    }
    return Json(new { result = ret, responseText = "Synchronization started." });
}

没有async/await：

public JsonResult ProcessSynchronization(int sourceId, string[] cities)
{
    var ret = false;
    try
    {              

        if (sourceId == 1)
        { 
            var cityDeep = (string[])cities.Clone();
            Logger.Info("ABout to start BeginSynchronization ..");

            var thread = new Thread(() =>
            {
                Logger.Info("ABout to start BeginSynchronization enter..");

                BeginSynchronization(cityDeep);
            });
            thread.Start();


            ret = true;
        }

    }
    catch (Exception ex)
    {
        Logger.Error(LogUtility.BuildExceptionMessage(ex), ex);
        return Json(new { result = ret, responseText = "Customer could not be activated." });
    }
    return Json(new { result = ret, responseText = "Synchronization started." });
}