如何让线程在另一个类中等待dataReceived事件

Question

我有一个程序，它创建数据包并将它们放入一个队列中，并使用一个单独的线程检查队列，如果有数据，它通过串行连接发送它，否则它会等待一点并再次检查。问题是如果我一次发送太多数据然后不响应，我发送的设备将不堪重负。为了解决这个问题，我需要让我的传输线程等到我从设备收到一个完整的数据包，所以在DataReceived事件中我检查我是否收到了整个数据包，如果有，它会被解析，我想发信号通知发送线程可以发送另一个数据包，否则，我想等待其余的数据，而不用发信号通知发送线程。

这是我的传输线程

Private Sub TxThread()
    While Not abortThread
        While (Not abortThread) AndAlso (txQueue.Count = 0)
            Thread.Sleep(500)
        End While

        mPort.SendCommand(txQueue.Dequeue())

        ''''
        '''' Wait for signal that entire packet received
        ''''

    End While
End Sub

这是我的DataReceived

Private Sub mPort_DataReceived(sender As Object, e As SerialDataReceivedEventArgs) Handles mPort.DataReceived
    ' Checks to see if enough data has been received to check for the Preamble
    If mPort.BytesToRead >= 2 And mPort.IsOpen Then
        ' Stores the string received into the packet variable
        packet &= mPort.ReadExisting()

        ' Checks to see if the string starts with the correct preamble
        If packet.StartsWith(ToCharacters(CommandStringBuilder.PREAMBLE)) Then
            PreambleReceived()

        ElseIf packet.Contains(ToCharacters(CommandStringBuilder.PREAMBLE)) Then
            ' If the data doesn't start with a preamble but it contains one, then it cuts off everything before the preamble and 
            ' checks to see if it is long enough to get the length byte
            packet = packet.Remove(0, packet.IndexOf(ToCharacters(CommandStringBuilder.PREAMBLE)))
            ' If it is long enough, then it checks if it has the whole string using the length byte and the actual length
            PreambleReceived()
        Else
            ' If the data doesn't contain the preamble then discard the string and reset rxData
            packet = ""
        End If
    End If
End Sub

Private Sub PreambleReceived()
    ' If the string is long enough, check the length byte in the string
    If packet.Length > 8 Then
        ' Calls a function I defined to test the number of bytes I received vs the number of bytes I expect and returns the difference
        Dim bytesEqual As Byte = GetBytesReceived()

        ' If the length byte and the actual length match, then the entire string has been received and can be sent for parsing
        If bytesEqual = 0 Then

            ''''
            '''' Signal entire packet received
            ''''

            packet = ""

            ' If the actual length is greater than the bytes expected then check to see if the string contains another preamble
            ' and if it does, cut off and discard everything after and including the second preamble, if not then it discards the data
        ElseIf bytesEqual < 0 Then
            If packet.Substring(3).Contains(ToCharacters(CommandStringBuilder.PREAMBLE)) Then
                Dim receivedTextBuffer As String
                Dim startIndex As Integer = packet.IndexOf(ToCharacters(CommandStringBuilder.PREAMBLE), 3)

                ' Gets the index of the preamble starting at index 3 and removes it and everything after it
                receivedTextBuffer = packet.Substring(startIndex)
                packet = packet.Remove(startIndex)

                ''''
                '''' Signal entire packet received
                ''''

                packet = receivedTextBuffer
            Else
                ' If packet doesn't contain a preamble, then discard the data and reset
                packet = ""
            End If
            ' If the bytes expected > bytes received then exit without resetting anything and wait for more data
        End If
        ' If the length isn't long enough to see the length byte yet, exit without resetting anything and wait for more data
    End If
End Sub

值得注意的是，TxThread和带有PreambleReceived的DataReceived位于不同的类中，因此TxThread中的mPort与DataReceived中的mPort不同。