是否可以创建有限数量的线程来发送 webRequest？-解网

问：

我有以下代码：

Friend Function SendToServer(ByVal Datos As List(Of String), ByVal User As String, ByVal Password As String) As String

    Dim ErrorCount As Integer = 0

    BGW_Report("Sending " & Datos.Count.ToString & " event(s).", Color.Purple)

    Try
        For Each Eventox As String In Datos
            Dim data = Encoding.UTF8.GetBytes(Eventox)

            Dim xUri As New Uri(My.Settings.WebAddress)
            Dim result_post = SendRequest(xUri, data, "application/json", "POST")

            If Not result_post.Contains("Process OK") Then
                ErrorCount += 1
            End If
        Next

    Catch ex As Exception

        BGW_Report("ErrorCount: " & ErrorCount, Color.Red)
        BGW_Report(ex.Message, Color.Red)
        BGW_Report(ex.StackTrace, Color.OrangeRed)

        ErrorCount = -1
    End Try

    Return ErrorCount

End Function

Private Function SendRequest(uri As Uri, jsonDataBytes As Byte(), contentType As String, method As String) As String
    Dim response As String
    Dim request As WebRequest

    request = WebRequest.Create(uri)
    request.ContentLength = jsonDataBytes.Length
    request.ContentType = contentType
    request.Method = method
   
    Using requestStream = request.GetRequestStream
        requestStream.Write(jsonDataBytes, 0, jsonDataBytes.Length)
        requestStream.Close()

        Using responseStream = request.GetResponse.GetResponseStream
            Using reader As New StreamReader(responseStream)
                response = reader.ReadToEnd()
            End Using
        End Using
    End Using

    Return response
End Function

这个 Web 请求大约需要半秒钟才能回答，并且我有几份报告要发送，所以我正在考虑在例程中创建多个线程，但最多限制为 20 个。For Each

我该怎么做？

我是多线程的新手;我从来没有用过超过两个.BackgroundWorkers

我正在使用 BackgroundWorker 调用函数 SendToServer。

网络框架 4.0 VS2022

vb.net 多线程

Public Sub startThreads()
    For i=0 To 20

        Dim threadParams As New ThreadParams
        threadParams.uri=...
        threadParams.jsonDataBytes=...
        threadParams.contentType=...
        threadParams.method=...

        Dim thr As New Thread(AddressOf ThreadSub)
        thr.Start(threadParams)
    Next
End Sub

我希望它有所帮助。

如果变量可在 ThreadSub 中访问，则该变量可在线程内部访问。但是，对同一变量的并行修改可能会导致不可预测的结果。您应该在 Invoke 中执行此操作。例如。MyForm.Invoke（Sub（） ErrorCount+=1 End Sub）。问题在于，您不知道何时应该检查 ErrorCount 变量以获取最终结果。顺便说一句，为什么不创建一个 sub 来创建一个 Background Worker 并在 for 循环中调用它呢？

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是否可以创建有限数量的线程来发送 webRequest？

Is it possible to create a limited number of threads to send a webRequest?

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