如何使用为VB编写的dll.Net中的c#

Question

我有个问题要问。

我有一个dll文件写入读取和写入USB上的数据。在VB中使用dll。. Net，一个需要集成的。vb文件的接口说明DLL文件要使用它的函数、属性等。

我需要的是在c#项目中使用这个dll。这可能吗?如果是，我该如何实现它?

形式的代码Class:

Public Class frmUSB
    ' vendor and product IDs
    Private Const VendorID As Integer = &H1234    'Replace with your device's
    Private Const ProductID As Integer = &H1234      'product and vendor IDs
    ' read and write buffers
    Private Const BufferInSize As Integer = 1 'Size of the data buffer coming IN to the PC
    Private Const BufferOutSize As Integer = 1    'Size of the data buffer going OUT from the PC
    Dim BufferIn(BufferInSize) As Byte          'Received data will be stored here - the first byte in the array is unused
    Dim BufferOut(BufferOutSize) As Byte    'Transmitted data is stored here - the first item in the array must be 0
    ' ****************************************************************
    ' when the form loads, connect to the HID controller - pass
    ' the form window handle so that you can receive notification
    ' events...
    '*****************************************************************
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        ' do not remove!
        ConnectToHID(Me)
    End Sub
    '*****************************************************************
    ' disconnect from the HID controller...
    '*****************************************************************
    Private Sub Form1_FormClosed(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosedEventArgs) Handles Me.FormClosed
        DisconnectFromHID()
    End Sub
    '*****************************************************************
    ' a HID device has been plugged in...
    '*****************************************************************
    Public Sub OnPlugged(ByVal pHandle As Integer)
        If hidGetVendorID(pHandle) = VendorID And hidGetProductID(pHandle) = ProductID Then
            ' ** YOUR CODE HERE **
        End If
    End Sub
    '*****************************************************************
    ' a HID device has been unplugged...
    '*****************************************************************
    Public Sub OnUnplugged(ByVal pHandle As Integer)
        If hidGetVendorID(pHandle) = VendorID And hidGetProductID(pHandle) = ProductID Then
            hidSetReadNotify(hidGetHandle(VendorID, ProductID), False)
            ' ** YOUR CODE HERE **
        End If
    End Sub
    '*****************************************************************
    ' controller changed notification - called
    ' after ALL HID devices are plugged or unplugged
    '*****************************************************************
    Public Sub OnChanged()
        ' get the handle of the device we are interested in, then set
        ' its read notify flag to true - this ensures you get a read
        ' notification message when there is some data to read...
        Dim pHandle As Integer
        pHandle = hidGetHandle(VendorID, ProductID)
        hidSetReadNotify(hidGetHandle(VendorID, ProductID), True)
    End Sub
    '*****************************************************************
    ' on read event...
    '*****************************************************************
    Public Sub OnRead(ByVal pHandle As Integer)
        ' read the data (don't forget, pass the whole array)...
        If hidRead(pHandle, BufferIn(0)) Then
            TextBox1.Text = Str(BufferIn(1))
            ' ** YOUR CODE HERE **
            ' first byte is the report ID, e.g. BufferIn(0)
            ' the other bytes are the data from the microcontroller...
        End If
    End Sub
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        BufferOut(1) = Val(TextBox2.Text)
        hidWriteEx(VendorID, ProductID, BufferOut(0))
    End Sub
End Class

我可以使用什么来发送我的表单实例到HIDDLLInterface(等价于Me关键字)?

接口类代码如下:

导入系统导入系统。线程进口System.Runtime.InteropServices

Module HIDDLLInterface
    ' this is the interface to the HID controller DLL - you should not
    ' normally need to change anything in this file.
    '
    ' WinProc() calls your main form 'event' procedures - these are currently
    ' set to..
    '
    ' MainForm.OnPlugged(ByVal pHandle as long)
    ' MainForm.OnUnplugged(ByVal pHandle as long)
    ' MainForm.OnChanged()
    ' MainForm.OnRead(ByVal pHandle as long)

    ' HID interface API declarations...
    Declare Function hidConnect Lib "mcHID.dll" Alias "Connect" (ByVal pHostWin As Integer) As Boolean
    Declare Function hidDisconnect Lib "mcHID.dll" Alias "Disconnect" () As Boolean
    Declare Function hidGetItem Lib "mcHID.dll" Alias "GetItem" (ByVal pIndex As Integer) As Integer
    Declare Function hidGetItemCount Lib "mcHID.dll" Alias "GetItemCount" () As Integer
    Declare Function hidRead Lib "mcHID.dll" Alias "Read" (ByVal pHandle As Integer, ByRef pData As Byte) As Boolean
    Declare Function hidWrite Lib "mcHID.dll" Alias "Write" (ByVal pHandle As Integer, ByRef pData As Byte) As Boolean
    Declare Function hidReadEx Lib "mcHID.dll" Alias "ReadEx" (ByVal pVendorID As Integer, ByVal pProductID As Integer, ByRef pData As Byte) As Boolean
    Declare Function hidWriteEx Lib "mcHID.dll" Alias "WriteEx" (ByVal pVendorID As Integer, ByVal pProductID As Integer, ByRef pData As Byte) As Boolean
    Declare Function hidGetHandle Lib "mcHID.dll" Alias "GetHandle" (ByVal pVendoID As Integer, ByVal pProductID As Integer) As Integer
    Declare Function hidGetVendorID Lib "mcHID.dll" Alias "GetVendorID" (ByVal pHandle As Integer) As Integer
    Declare Function hidGetProductID Lib "mcHID.dll" Alias "GetProductID" (ByVal pHandle As Integer) As Integer
    Declare Function hidGetVersion Lib "mcHID.dll" Alias "GetVersion" (ByVal pHandle As Integer) As Integer
    Declare Function hidGetVendorName Lib "mcHID.dll" Alias "GetVendorName" (ByVal pHandle As Integer, ByVal pText As String, ByVal pLen As Integer) As Integer
    Declare Function hidGetProductName Lib "mcHID.dll" Alias "GetProductName" (ByVal pHandle As Integer, ByVal pText As String, ByVal pLen As Integer) As Integer
    Declare Function hidGetSerialNumber Lib "mcHID.dll" Alias "GetSerialNumber" (ByVal pHandle As Integer, ByVal pText As String, ByVal pLen As Integer) As Integer
    Declare Function hidGetInputReportLength Lib "mcHID.dll" Alias "GetInputReportLength" (ByVal pHandle As Integer) As Integer
    Declare Function hidGetOutputReportLength Lib "mcHID.dll" Alias "GetOutputReportLength" (ByVal pHandle As Integer) As Integer
    Declare Sub hidSetReadNotify Lib "mcHID.dll" Alias "SetReadNotify" (ByVal pHandle As Integer, ByVal pValue As Boolean)
    Declare Function hidIsReadNotifyEnabled Lib "mcHID.dll" Alias "IsReadNotifyEnabled" (ByVal pHandle As Integer) As Boolean
    Declare Function hidIsAvailable Lib "mcHID.dll" Alias "IsAvailable" (ByVal pVendorID As Integer, ByVal pProductID As Integer) As Boolean
    ' windows API declarations - used to set up messaging...
    Public Declare Function CallWindowProc Lib "user32" Alias "CallWindowProcA" (ByVal lpPrevWndFunc As Integer, ByVal hwnd As Integer, ByVal Msg As Integer, ByVal wParam As Integer, ByVal lParam As Integer) As Integer
    Public Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" _
                                          (ByVal hwnd As Integer, ByVal nIndex As Integer, ByVal dwNewLong As Integer) As Integer
    Delegate Function SubClassProcDelegate(ByVal hwnd As Integer, ByVal msg As Integer, ByVal wParam As Integer, ByVal lParam As Integer) As Integer
    Public Declare Function DelegateSetWindowLong Lib "USER32.DLL" Alias "SetWindowLongA" _
                                           (ByVal hwnd As Integer, ByVal attr As Integer, ByVal lval As SubClassProcDelegate) As Integer

    ' windows API Constants
    Public Const WM_APP As Integer = 32768
    Public Const GWL_WNDPROC As Short = -4
    ' HID message constants
    Private Const WM_HID_EVENT As Decimal = WM_APP + 200
    Private Const NOTIFY_PLUGGED As Short = 1
    Private Const NOTIFY_UNPLUGGED As Short = 2
    Private Const NOTIFY_CHANGED As Short = 3
    Private Const NOTIFY_READ As Short = 4
    ' local variables
    Private FPrevWinProc As Integer ' Handle to previous window procedure
    Private FWinHandle As Integer ' Handle to message window
    Private Ref_WinProc As New SubClassProcDelegate(AddressOf WinProc)
    Private HostForm As Object
    ' Set up a windows hook to receive notification
    ' messages from the HID controller DLL - then connect
    ' to the controller
    Public Function ConnectToHID(ByRef targetForm As Form) As Boolean
        Dim pHostWin As Integer = targetForm.Handle.ToInt32
        FWinHandle = pHostWin
        pHostWin = hidConnect(FWinHandle)
        FPrevWinProc = DelegateSetWindowLong(FWinHandle, GWL_WNDPROC, Ref_WinProc)
        HostForm = targetForm
    End Function
    ' Unhook from the HID controller and disconnect...
    Public Function DisconnectFromHID() As Boolean
        DisconnectFromHID = hidDisconnect
        SetWindowLong(FWinHandle, GWL_WNDPROC, FPrevWinProc)
    End Function

    ' This is the procedure that intercepts the HID controller messages...
    Private Function WinProc(ByVal pHWnd As Integer, ByVal pMsg As Integer, ByVal wParam As Integer, ByVal lParam As Integer) As Integer
        If pMsg = WM_HID_EVENT Then
            Select Case wParam
                ' HID device has been plugged message...
                Case Is = NOTIFY_PLUGGED
                    HostForm.OnPlugged(lParam)
                    ' HID device has been unplugged
                Case Is = NOTIFY_UNPLUGGED
                    HostForm.OnUnplugged(lParam)
                    ' controller has changed...
                Case Is = NOTIFY_CHANGED
                    HostForm.OnChanged()
                    ' read event...
                Case Is = NOTIFY_READ
                    HostForm.OnRead(lParam)
            End Select
        End If
        ' next...
        WinProc = CallWindowProc(FPrevWinProc, pHWnd, pMsg, wParam, lParam)
    End Function
End Module

Answer 1

假设VB。. NET代码是CLS兼容的，你可以简单地添加一个引用到你的c#项目。

此时，DLL中的命名空间和所有公共成员将对c#代码可用。

Answer 2

您的设计中存在耦合问题。为了解决这个问题，我的建议如下:

• 将HIDDLLInterface转换为在构造函数中接受IntPtr的类。在构造函数中调用hidConnect。
• 使类实现IDisposable。VB IDE提供了一个不错的默认实现。因为你正在处理非托管资源，你可能还应该取消注释它添加的终结器。
• 不再从dll接口调用表单方法，而是在相应消息传入时引发事件。
检查你的PInvoke签名。如果参数名称中有"handle"，或者在本机dll中声明为HWND或Hsomething，则应该使用IntPtr而不是Integer来更接近参数的含义。
• 你也可以考虑在新类上提供额外的方法，并在类中完全封装所有的"Declare"函数，但这超出了这个问题的范围。

之后，类应该看起来像这样:

Public Class HIDController
    Implements IDisposable
#Region "Constructor"
    Public Sub New(handle As IntPtr)
        If Not hidConnect(handle) Then
            'consider a custom exception type here.  You may also get
            'more info about the failure from GetLastError.
            Throw New Exception("Connection failed")
        End If
        _handle = handle
        _prevWinProc = DelegateSetWindowLong(handle, GWL_WNDPROC, AddressOf Me.WinProc)
    End Sub
#End Region
#Region "IDisposable Support"
    Private disposedValue As Boolean 
    Protected Overridable Sub Dispose(disposing As Boolean)
        If Not Me.disposedValue Then
            If disposing Then
                ' TODO: dispose managed state (managed objects).
            End If
            ' TODO: free unmanaged resources (unmanaged objects) and override Finalize() below.
            DisconnectFromHID()
        End If
        Me.disposedValue = True
    End Sub
    Protected Overrides Sub Finalize()
        Dispose(False)
        MyBase.Finalize()
    End Sub
    Public Sub Dispose() Implements IDisposable.Dispose
        Dispose(True)
        GC.SuppressFinalize(Me)
    End Sub
#End Region
    Private _handle As IntPtr
    Private ReadOnly _prevWinProc As IntPtr
    'on one hand, you are not supposed to throw from Dispose/Finalize, but
    'on the other hand, I don't know what you would do instead to signal failure.
    Private Sub DisconnectFromHID()
        'do not disconnect if you did not connect
        If _handle = IntPtr.Zero Then Exit Sub
        If Not hidDisconnect() Then
            'see above about custom exception type
            Throw New Exception("Disconnect failed")
        End If
        SetWindowLong(_handle, GWL_WNDPROC, _prevWinProc)
        _handle = IntPtr.Zero
    End Sub
    Private Function WinProc(ByVal pHWnd As IntPtr, ByVal pMsg As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As Integer
        If pMsg = WM_HID_EVENT Then
            Select Case wParam.ToInt32()
                Case NOTIFY_PLUGGED
                    OnPlugged(lParam)
                Case NOTIFY_UNPLUGGED
                    OnUnplugged(lParam)
                Case NOTIFY_CHANGED
                    OnChanged()
                Case NOTIFY_READ
                    OnRead(lParam)
            End Select
        End If
        WinProc = CallWindowProc(FPrevWinProc, pHWnd, pMsg, wParam, lParam)
    End Function
#Region "USB events"
    Private Sub OnPlugged(lParam As IntPtr)
        RaiseEvent Plugged(Me, New ParamEventArgs(lParam))
    End Sub
    Public Event Plugged As EventHandler(Of ParamEventArgs)
    Private Sub OnUnplugged(lParam As IntPtr)
        RaiseEvent Unplugged(Me, New ParamEventArgs(lParam))
    End Sub
    Public Event Unplugged As EventHandler(Of ParamEventArgs)
    Private Sub OnChanged()
        RaiseEvent Changed(Me, EventArgs.Empty)
    End Sub
    Public Event Changed As EventHandler
    Private Sub OnRead(lParam As IntPtr)
        RaiseEvent Read(Me, New ParamEventArgs(lParam))
    End Sub
    Public Event Read As EventHandler(Of ParamEventArgs)
#End Region
    'other constants and declarations I did not copy.
End Class
Public Class ParamEventArgs
    Inherits EventArgs
    Public Sub New(param As IntPtr)
        _param = param
    End Sub
    Private _param As IntPtr
    Public ReadOnly Property Param() As IntPtr
        Get
            Return _param
        End Get
    End Property
End Class

从那里，你可以改变你的表单，在Load/Close事件中创建和处置该类的一个实例，并挂钩处理程序。您必须更改表单方法以匹配事件签名，但这应该很简单。

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    _controller = new HIDController(Me.Handle)
    AddHandler _controller.Plugged, AddressOf Me.OnPlugged
    'similarly for other events
End Sub
Private Sub Form1_FormClosed(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosedEventArgs) Handles Me.FormClosed
    If _controller IsNot Nothing Then _controller.Dispose()
End Sub

现在这个类应该很容易在c# dll中使用。只需在VB中将HIDController编译成程序集。. NET，然后从c#项目中引用该dll(并导入任何所需的命名空间)。不要忘记复制本地dll;c#编译器只会自动复制VB的dll。任何可以提供窗口句柄的类现在都可以创建HIDController并处理其事件，而无需控制器知道是哪个类承载它。

PS:我建议在VB中编码时打开Option Strict。此外，您可能想要查看DllImport，以将函数从本机库导入到。net项目中，因为这是大多数示例的方式，并且将使VB和c#之间的复制更容易。

Answer 3

在VB项目中引用c# dll(或者只是将dll放入/bin文件夹中)

如你所知，你需要适应VB。NET代码中的窗体类到c#。

在回答你的问题，而不是从VB调用。. NET表单代码隐藏:

iConnectToHID(Me)

使用

iConnectToHID(this);