2017-04-10 85 views
0

我是VB新手,我試圖讓程序輸出文本而不是十六進制。我在網上找到了這個代碼,這個程序叫做maxiCOM。這裏是鏈接http://www.innovatic.dk/knowledg/SerialCOM/SerialCOM.htm。源代碼可以在頁面底部下載。

不幸的是,程序中的編碼水平遠遠高於我的理解水平,而且我也沒有真正知道如何將輸出從十六進制改爲文本。如果有人能向我解釋如何做到這一點,我將不勝感激。代碼的片段是將字節轉換爲Visual Basic中的字符串

Public Class MaxiTester 

Dim SpaceCount As Byte = 0 
Dim LookUpTable As String = "ABCDEF" 
Dim RXArray(2047) As Char ' Text buffer. Must be global to be accessible from more threads. 
Dim RXCnt As Integer  ' Length of text buffer. Must be global too. 

' Make a new System.IO.Ports.SerialPort instance, which is able to fire events. 
Dim WithEvents COMPort As New SerialPort 

Private Sub Receiver(ByVal sender As Object, ByVal e As SerialDataReceivedEventArgs) Handles COMPort.DataReceived 
    Dim RXByte As Byte 
    Do 
     '----- Start of communication protocol handling ----------------------------------------------------------- 
     ' The code between the two lines does the communication protocol. In this case, it simply emties the 
     ' receive buffer and converts it to text, but for all practical applications, you must replace this part 
     '  with a code, which can collect one entire telegram by searching for the telegram 
     '  delimiter/termination. In case of a simple ASCII protocol, you may just use ReadLine and receive 
     '   in a global string instead of a byte array. 
     ' Because this routine runs on a thread pool thread, it does not block the UI, so if you have any data 
     ' convertion, encryption, expansion, error detection, error correction etc. to do, do it here. 
     RXCnt = 0 
     Do 
      RXByte = COMPort.ReadByte 
      RXArray(RXCnt) = LookUpTable(RXByte >> 4) ' Convert each byte to two hexadecimal characters 
      RXCnt = RXCnt + 1 
      RXArray(RXCnt) = LookUpTable(RXByte And 15) 
      RXCnt = RXCnt + 1 
      RXArray(RXCnt) = " " 
      RXCnt = RXCnt + 1 
      SpaceCount = (SpaceCount + 1) And 31  ' Insert spaces and CRLF for better readability 
      If SpaceCount = 0 Then     ' Insert CRLF after 32 numbers 
       RXArray(RXCnt) = Chr(13) ' CR 
       RXCnt = RXCnt + 1 
       RXArray(RXCnt) = Chr(10) ' LF 
       RXCnt = RXCnt + 1 
      Else 
       If (SpaceCount And 3) = 0 Then  ' Insert two extra spaces for each 4 numbers 
        RXArray(RXCnt) = " " 
        RXCnt = RXCnt + 1 
        RXArray(RXCnt) = " " 
        RXCnt = RXCnt + 1 
       End If 
      End If 
     Loop Until (COMPort.BytesToRead = 0) 
     '----- End of communication protocol handling ------------------------------------------------------------- 
     Me.Invoke(New MethodInvoker(AddressOf Display)) ' Start "Display" on the UI thread 
    Loop Until (COMPort.BytesToRead = 0) ' Don't return if more bytes have become available in the meantime 
End Sub 

' Text display routine, which appends the received string to any text in the Received TextBox. 

Private Sub Display() 
    Received.AppendText(New String(RXArray, 0, RXCnt)) 
End Sub 

回答

0

在內環Do後的第一行通知:

RXByte = COMPort.ReadByte 

這是讀你的代碼只點了,你有實際字節值來自COM端口。在此之後,代碼使用位移將該字節轉換爲兩個十六進制值。您應該創建一個全局變量string類型,並在其丟失之前將讀取的字節值附加到該字符串。

立即添加以下行上面的行之後:

YourString &= Convert.ToChar(RXByte).ToString() 

其中YourString是全局變量string

請注意,您可以通過使用StringBuilder而不是string來獲得一些效率,但是我將此練習留給您。

+0

感謝您的幫助!按照您的指示並修改了一些顯示程序後,我才能使用它。 –

-1
System.Text.Encoding.Unicode.GetString(bytes) 'bytes is your byte array' 
+2

你應該解釋一下這個一行代碼如何適合OP的情況。 – dotNET

+1

@dotNET有機會他們沒有讀到這個問題,只是標題。 – Jaxi

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