如何检索连接到USB端口的USB设备的端口号？

Question

如何使用VB6检索连接到USB端口的USB设备的端口号？我可以说： \\?\USB#Vid_0801&Pid_2250#7&91e2848&0&1#{4d36e978-e325-11ce-bfc1-08002be10318}

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

Answer 1

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/

Answer 2

查看可用的相称，你可以使用：

'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 

在该列表中你可以标记你已经知道的端口，所以其他应是USB设备的端口

请注意：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