.net - 寻找丑陋的多线程的标准替代品

Question

我一直在尝试不同的方式来异步处理数据。我有一段代码可以在图像处理应用程序中完成这样的任务，但对我来说似乎很尴尬。我正在寻找符合当前标准或要遵循的编码约定的建议:

' this code is run on a background thread
Dim lockThreadCounter As New Object()
Dim runningThreadCounter As Integer = 0
Dim decrementCounterCallback As New AsyncCallback(
    Sub()
        SyncLock lockThreadCounter
            runningThreadCounter -= 1
        End SyncLock
    End Sub)
runningThreadCounter += 1
widthsAdder.BeginInvoke(widthsSlow, decrementCounterCallback, Nothing)
runningThreadCounter += 1
widthsAdder.BeginInvoke(widthsFast, decrementCounterCallback, Nothing)
runningThreadCounter += 1
bruteForceCalculateR2.BeginInvoke(numberOfSamples, pixelsSlow, decrementCounterCallback, Nothing)
runningThreadCounter += 1
bruteForceCalculateR2.BeginInvoke(numberOfSamples, pixelsFast, decrementCounterCallback, Nothing)
' wait here for all four tasks to complete
While runningThreadCounter > 0
    Thread.Sleep(1)
End While
' resume with the rest of the code once all four tasks have completed

我考虑过 Parallel.Foreach 但无法想出使用它的解决方案，因为任务具有不同的委托(delegate)足迹。

Answer 1

您可以使用 Task类开始你的工作，和Task.WaitAll等待他们完成。

这消除了“运行线程计数器”的需要，因为每个任务都可以作为一个组存储和等待。

这看起来像(一旦你删除了你的回调):

Dim widths1 = Task.Factory.StartNew(Sub() widthsSlow())
Dim widths2 = Task.Factory.StartNew(Sub() widthsFast())
Dim bruteForce1 = Task.Factory.StartNew(Sub() numberOfSamples(pixelsSlow))
Dim bruteForce2 = Task.Factory.StartNew(Sub() numberOfSamples(pixelsFast))

' Wait for all to complete without the loop
Task.WaitAll(widths1, widths2, bruteForce1, bruteForce2)