.NET线程不是分开的吗? [英] .NET Threads are not separate?

问题描述

我有一个可获取视频文件时长的子项.

I have a sub which gets the duration of a video file.

Async Sub GetDuration(folder As String)

Dim ffP As New FFProbe
Dim vInfo As MediaInfo

Dim totalSecs As Double = Await Task.Run(Function()
                                           vInfo = ffP.GetMediaInfo(filep)
                                           If vInfo.Duration.TotalSeconds < 10
                                            Thread.Sleep(20000)
                                           End If
                                           Return vInfo.Duration.TotalSeconds
                                         End Function)

当我在短视频(少于10秒)中运行此程序时，它会按预期使应用程序休眠20秒.但是，在浏览器的另一个选项卡上，我在一个长视频(大于10秒)上运行它，而第一个线程仍在睡眠中……但是它也睡眠了，直到20秒过期/过去了.因此，两个选项卡都处于睡眠状态，这向我表明它们确实是同一线程.使用Async/Await对时，VB.NET是否不应该创建单独的线程吗?

When I run this on a short video (less than 10 seconds), it sleeps the application for 20 seconds, as expected. On another tab in the browser, however, I run it on a long video (greater than 10 seconds), while the first thread is still sleeping...but it sleeps, too, until the 20 seconds has expired/passed. So both tabs are sleeping, which indicates to me that they are really the same thread. Isn't VB.NET supposed to create separate threads when using the Async/Await pair?

主要思想是让它们分别运行，以便多个用户可以彼此独立获得持续时间.

The main idea was to have them run separately, so multiple users can get duration independently of each other.

推荐答案

异步和等待模式不是多线程的.使用相同的线程，但是以某种方式调度了该线程中的进程，以使该线程不会被锁定.在VS中，您可以检查调试期间正在运行的线程.

Async and await patterns are not multithreading. The same thread is used, but the processes in that thread are scheduled in a way so that the thread is not locked. In VS, you can inspect the threads you have running during debug.

这篇关于.NET线程不是分开的吗?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！