我必须使用多个大的二维数组(例如1024 x 128),在我的代码的一部分中,我需要转置一些(最多12个)。 该过程需要相当长的时间,我试图尽可能加快速度。知道VB.NET支持多线程我在这里和那里读了不同的源,并且可以在主子例程中提出以下代码:
RunXTransposingThreads(Arr1, Arr2, Arr3, ...)
使用BackgroundWorker
作为我的解决方案的一部分:
Private Sub RunXTransposingThreads(ParamArray ArraysToTranspose() As Array)
Dim x = CInt(ArraysToTranspose.GetLength(0)) - 1
Dim i As Integer
For i = 0 To x
Dim worker As New System.ComponentModel.BackgroundWorker
AddHandler worker.DoWork, AddressOf RunOneThread
AddHandler worker.RunWorkerCompleted, AddressOf HandleThreadCompletion
worker.RunWorkerAsync(ArraysToTranspose(i))
Next
End Sub
Private Sub RunOneThread(ByVal sender As System.Object, ByVal e As System.ComponentModel.DoWorkEventArgs)
Dim Transposed(,) As Single = Array.CreateInstance(GetType(Single), 0, 0) ' I need this to be like that in order to use other functions later
Transposed = Transpose2dArray(CType(e.Argument, Single(,)))
e.Result = Transposed
End Sub
Private Sub HandleThreadCompletion(ByVal sender As Object, ByVal e As System.ComponentModel.RunWorkerCompletedEventArgs)
Debug.Print("Process complete")
End Sub
Function Transpose2dArray(Of Array)(ByVal inArray As Array(,)) As Array(,)
Dim x = CInt(inArray.GetLength(1))
Dim y = CInt(inArray.GetLength(0))
Dim outArray(x - 1, y - 1) As Array
For i = 0 To x - 1
For j = 0 To y - 1
outArray(i, j) = inArray(j, i)
Next
Next
Transpose2dArray = outArray
End Function
线程似乎有效,因为在执行RunXTransposingThreads
之后某些时候,我在屏幕上看到了一些"处理完成"。问题是:如果我还没有转换数组,如何停止执行主代码?
答案 0 :(得分:2)
正如其他人所说,BackgroundWorker已经过时了。幸运的是,还有许多其他现代方法可以做到这一点。
因此,我不会向您展示使您的代码与BackgroundWorker一起使用的内容。相反,我将通过使用任务,一种现代方式向您展示如何做同样的事情。希望它有所帮助。
Function RunXTransposingTasks(ParamArray ArraysToTranspose() As Array) As Array
Dim taskList = New List(Of Task(Of Single(,))) ' our tasks returns Arrays
For Each arr In ArraysToTranspose
Dim r = arr
taskList.Add(Task.Run(Function() Transpose2dArray(r)))
Next
Task.WhenAll(taskList) ' wait for all tasks to complete.
Return taskList.Select(Function(t) t.Result).ToArray()
End Function
Function Transpose2dArray(inArray As Array) As Single(,)
Dim x = inArray.GetLength(1) - 1
Dim y = inArray.GetLength(0) - 1
Dim outArray(x, y) As Single
For i = 0 To x
For j = 0 To y
outArray(i, j) = inArray(j, i)
Next
Next
Return outArray
End Function
' Usage
' Dim result = RunXTransposingTasks(Arr1, Arr2, Arr3, ...)
答案 1 :(得分:-1)
您可以尝试使用build-in function复制数据
Array.Copy(inArray, outArray, CInt(inArray.GetLength(1)) * CInt(inArray.GetLength(0)))
还有一些关于如何使用Parallel.ForEach的great example。