Question

如何使用VB6检索连接到USB端口的USB设备的端口号？我已经可以获得USB设备名称，让我们说： \\?\USB#Vid_0801&Pid_2250#7&91e2848&0&1#{4d36e978-e325-11ce-bfc1-08002be10318}

如何自动检测分配给它的端口号？我正在制作一个程序，它将自动确定连接到任何USB端口的特定设备的端口号，并自动开始在其上进行通信。

Answer 1

查看您可以使用的可用组件：

'1 form with :
'    1 combobox : name=Combo1
'    1 mscomm control : name=MSComm1

Option Explicit

Public Enum PortAttr
  PortFree = 0
  PortInUse = 1
  PortUnknown = 2
End Enum

Private Sub Form_Load()
  'show available ports
  ShowPorts
End Sub

Private Sub ShowPorts()
  Dim intIndex As Integer
  Dim intPort As Integer
  Dim intFree As Integer
  On Error GoTo ErrorFound
  With MSComm1
    If .PortOpen Then .PortOpen = False
    intPort = .CommPort
    Combo1.Clear
    Combo1.AddItem "--- Not Used ---"
    Combo1.ItemData(0) = -2 'not possible
    Combo1.AddItem "---- In Use ----"
    Combo1.ItemData(1) = -2 'not possible
    intFree = 0
    For intIndex = 1 To 10
      Select Case CheckPort(intIndex)
        Case PortFree
          intFree = intFree + 1
          Combo1.AddItem "Com" & CStr(intIndex), intFree
          Combo1.ItemData(intFree) = intIndex
        Case PortInUse
          Combo1.AddItem "Com" & CStr(intIndex)
      End Select
    Next intIndex
    If .PortOpen Then .PortOpen = False
    .CommPort = intPort
    If CheckPort(intPort) = PortFree Then
      If .PortOpen = False Then .PortOpen = True
    End If
  End With 'MSComm1
Exit Sub
ErrorFound:
  MsgBox Err.Description, vbCritical, "Error " & CStr(Err.Number)
  On Error GoTo 0
End Sub

Private Function CheckPort(intPort As Integer) As PortAttr
  On Error GoTo ErrorFound
  With MSComm1
    If .PortOpen Then .PortOpen = False
    .CommPort = intPort
    .PortOpen = True
    CheckPort = PortFree
    If .PortOpen = False Then .PortOpen = True
  End With 'MSComm1
Exit Function
ErrorFound:
  Select Case Err.Number
    Case 8002 'port doesnt exist
      CheckPort = PortUnknown
    Case 8005 'port already in use
      CheckPort = PortInUse
  End Select
  On Error GoTo 0
End Function

在该列表中，您可以标记您已经知道的端口，因此其他端口应该是USB设备的端口

注意：当USB设备通过另一个USB端口连接时，转换后的rs232端口也可能是另一个端口

Answer 2

这家伙有一些有用的脚本： http://todbot.com/blog/2012/03/02/listcomports-windows-command-line-tool-for-usb-to-serial/

如何检索连接到USB端口的USB设备的端口号？

2 个答案: