如何使用Microsoft Access与Visual Basic建立网络连接？

Question

我们有一个Microsoft Access内部的Visual Basic应用程序，我们需要建立一个网络连接。使用VB6，有一个称为WinSock的方便的小控件使得这一切成为可能，但是我无法找到任何与Microsoft Access中存在的精简版VB版本类似的东西。有任何想法吗？

由于我没有得到任何答案，我会尝试澄清我需要这个。

我的应用程序发出一封电子邮件，我们目前使用内置的Outlook对象来创建一条消息并在后台发送。缺点是它会提示用户批准“外部程序”发送电子邮件，这令我们的用户感到沮丧，似乎没有必要。我在网上找到的所有其他电子邮件选项都要求我们下载或购买控件，这对我们部署给所有用户来说太劳动密集了。

我一直希望使用套接字控件来手动连接到SMTP服务器并发送消息（因为这在其他语言中是微不足道的），但我找不到任何方法在VBA中建立TCP连接。

Answer 1

我刚刚在上个月处理了这个问题。由于各种原因，CDO不够用，直接使用MAPI方式太复杂，Outlook提示你抱怨完全无法接受。

我结束了使用Outlook Redemption。它被Access开发人员广泛使用，但我发现它相当复杂，并且没有很好的记录。但它做得很好。

Answer 2

微软添加的电子邮件“安全”功能使许多开发人员感到沮丧。我不知道一个优雅的解决方案。我已经成功地使用了免费软件ClickYes Express，但当然这不是您寻求的答案。

Answer 3

对于OP中提到的具体问题，有一个更好的解决方案。将邮件“保存”到Outlook。不要'发送'它。它可以让用户明确地控制发送的内容，以及何时和不生成弹出对话框。三赢。

但既然你问....

Option Explicit 

Public Const AF_INET = 2 'internetwork: UDP, TCP, etc. 
Public Const SOCK_STREAM = 1 'Stream socket 
Public Const SOCKET_ERROR = -1 

Type sockaddr_in 
    sin_family As Integer 
    sin_port As Integer 
    sin_addr As Long 
    sin_zero As String * 8 
End Type 

#If Win32 Then 

'for WSAStartup() function. 
Public Const WSADESCRIPTION_LEN = 256 
Public Const WSASYS_STATUS_LEN = 128 
Public Const WSA_DescriptionSize = WSADESCRIPTION_LEN + 1 
Public Const WSA_SysStatusSize = WSASYS_STATUS_LEN + 1 

Type wsaData 
    wVersion As Integer 
    wHighVersion As Integer 
    szDescription As String * WSA_DescriptionSize 
    szSystemStatus As String * WSA_SysStatusSize 
    iMaxSockets As Integer 
    iMaxUdpDg As Integer 
    lpVendorInfo As String * 200 
End Type 

#If Not VBA7 Then 
'Use this section for Excel 95 
Type Hostent 
    h_name As Long   '32 bit pointer 
    h_aliases As Long  '32 bit pointer 
    h_addrtype As Integer 'String * 2 (declared as short) 
    h_length As Integer  'String * 2 (declared as short) 
    h_addr_list As Long  '32 bit pointer 
End Type 

Public Declare Function closesocket Lib "ws2_32.dll" (ByVal s As Long) As Long 
Public Declare Function connect Lib "ws2_32.dll" (ByVal sID As Long, ByRef name As sockaddr_in, ByVal namelen As Long) As Long 
Public Declare Function htons Lib "ws2_32.dll" (ByVal hostshort As Integer) As Integer 
Public Declare Function inet_addr Lib "ws2_32.dll" (ByVal cp As String) As Long 
Public Declare Function recv Lib "ws2_32.dll" (ByVal s As Long, ByRef buf As Any, ByVal buflen As Long, ByVal flags As Long) As Long 
Public Declare Function recvstr Lib "ws2_32.dll" (ByVal s As Long, ByVal buf As Any, ByVal buflen As Long, ByVal flags As Long) As Long 
Public Declare Function send Lib "ws2_32.dll" (ByVal s As Long, ByRef buf As Any, ByVal buflen As Long, ByVal flags As Long) As Long 
Public Declare Function socket Lib "ws2_32.dll" (ByVal af As Long, ByVal s_type As Long, ByVal Protocol As Long) As Long 
Public Declare Function WSAStartup Lib "ws2_32.dll" (wVersionRequested As Integer, lpWSAData As wsaData) As Long 
Public Declare Function WSACleanup Lib "ws2_32.dll"() As Long 

'Public Declare Function setsockopt Lib "ws2_32.dll" (ByVal s As Long, ByVal level As Long, ByVal optname As Long, optval As Any, ByVal optlen As Long) As Long 
Public Declare Sub CopyMemory Lib "kernel32.dll" Alias "RtlMoveMemory" (ByRef Destination As Any, ByRef Source As Any, ByVal Length As Long) 
Public Declare Function gethostbyname Lib "ws2_32.dll" (ByVal host_name As String) As Long 

#Else 
'on Win64, ws2_32.dll in system32 has the file description "32-bit DLL" and uses 64bit pointers (morons) 
'on Win64 as on Win32, 32-bit numbers are called int. 
'on VBA7/64, as on VBA6/32, 32 bit numbers are called long. 
'delete following duplicate section for Excel 95 

Type Hostent 
    h_name As LongPtr  '32/64 bit pointer 
    h_aliases As LongPtr '32/64 bit pointer 
    h_addrtype As Integer 'String * 2 (declared as short) 
    h_length As Integer  'String * 2 (declared as short) 
    h_addr_list As LongPtr '32/64 bit pointer 
End Type 


Public Declare PtrSafe Function closesocket Lib "ws2_32.dll" (ByVal sID As LongPtr) As Long 
Public Declare PtrSafe Function connect Lib "ws2_32.dll" (ByVal sID As LongPtr, ByRef name As sockaddr_in, ByVal namelen As Long) As Long 
Public Declare PtrSafe Function htons Lib "ws2_32.dll" (ByVal hostshort As Integer) As Integer 
Public Declare PtrSafe Function inet_addr Lib "ws2_32.dll" (ByVal cp As String) As Long 
Public Declare PtrSafe Function recv Lib "ws2_32.dll" (ByVal sID As LongPtr, ByRef buf As Any, ByVal buflen As Long, ByVal flags As Long) As Long 
Public Declare PtrSafe Function recvstr Lib "ws2_32.dll" (ByVal sID As LongPtr, ByVal buf As Any, ByVal buflen As Long, ByVal flags As Long) As Long 
Public Declare PtrSafe Function send Lib "ws2_32.dll" (ByVal sID As LongPtr, ByRef buf As Any, ByVal buflen As Long, ByVal flags As Long) As Long 
Public Declare PtrSafe Function socket Lib "ws2_32.dll" (ByVal af As Long, ByVal s_type As Long, ByVal Protocol As Long) As Long 
Public Declare PtrSafe Function WSAStartup Lib "ws2_32.dll" (wVersionRequested As Integer, lpWSAData As wsaData) As Long 
Public Declare PtrSafe Function WSACleanup Lib "ws2_32.dll"() As Long 

'Public Declare PtrSafe Function setsockopt Lib "ws2_32.dll" (ByVal sID As Long, ByVal level As LongPtr, ByVal optname As Long, optval As Any, ByVal optlen As Long) As Long 
Public Declare PtrSafe Sub CopyMemory Lib "kernel32.dll" Alias "RtlMoveMemory" (ByRef Destination As Any, ByRef Source As Any, ByVal Length As LongPtr) 
Public Declare PtrSafe Function gethostbyname Lib "ws2_32.dll" (ByVal host_name As String) As LongPtr 


#End If 
#Else 
'OSX 
'delete following duplicate section for Excel 95 
'No 64bit version of Excel is available yet for the OSX 
Type Hostent 
    h_name As Long  '32 bit pointer 
    h_aliases As Long '32 bit pointer 
    h_addrtype As Long '32 bit int (declared as int) 
    h_length As Long '32 bit int (declared as int) 
    h_addr_list As Long '32 bit pointer 
End Type 

'ssize_t is a signed type. signed version of size_t, 
'used where a size may instead contain a negative error code 
'size_t is the unsigned integer type of the result of the sizeof operator 
'size_t is an unsigned integer type of at least 16 bit 

'or libsystem.dylib ? 
Public Declare Function socket Lib "libc.dylib" (ByVal af As Long, ByVal s_type As Long, ByVal Protocol As Long) As Long 
Public Declare Function connect Lib "libc.dylib" (ByVal s As Long, ByRef name As sockaddr_in, ByVal namelen As Long) As Long 
' or read ? 
Public Declare Function recv Lib "libc.dylib" (ByVal s As Long, buf As Any, ByVal buflen As Long, ByVal flags As Long) As Long 
Public Declare Function send Lib "libc.dylib" (ByVal s As Long, buf As Any, ByVal buflen As Long, ByVal flags As Long) As Long 
Public Declare Function htons Lib "libc.dylib" (ByVal Host_Short As Integer) As Integer 'x x x, but seems to work !!! 
Public Declare Function inet_addr Lib "libc.dylib" (ByVal cp As String) As Long 
Public Declare Function closesocket Lib "libc.dylib" Alias "close" (ByVal s As Long) As Long 
Public Declare Function setsockopt Lib "libc.dylib" (ByVal s As Long, ByVal level As Long, ByVal optname As Long, optval As Any, ByVal optlen As Long) As Long 
Public Declare Function gethostbyname Lib "libc.dylib" (ByVal host_name As String) As Long 
Public Declare Sub CopyMemory Lib "libc.dylib" Alias "memmove" (ByRef Destination As Any, ByRef Source As Any, ByVal Length As Long) 

#End If 

Private Function MyData(I_SocketAddress As sockaddr_in, Register As Integer, dataword As Long, serr As String) As Long 
Dim strSend  As String 
Dim count  As Integer 
Dim bArray() As Byte 
Dim errCode  As Integer 
Dim socketID As Long 

socketID = socket(AF_INET, SOCK_STREAM, 0) 
errCode = connect(socketID, I_SocketAddress, Len(I_SocketAddress)) 

count = send(socketID, ByVal strSend, Len(strSend), 0) 

If count <> Len(strSend) Then 
    errCode = -1 
    serr = "ERROR: network failure on send, " & Err.LastDllError() 
Else 
    count = RecvB(socketID, bArray, maxLength) 

    dodata bArray 
End If 
    DoEvents 
    Call closesocket(socketID) 
    MyData = errCode 
End Function 

Private Function RecvB(socketID As Long, bArray() As Byte, ByVal maxLength As Integer) As Integer 
Dim c As String * 1 
Dim b   As Byte 
Dim buf()  As Byte 
Dim Length  As Integer 
Dim count  As Long 
Dim i   As Integer 
Dim dStartTime As Variant 
Dim nErr  As Long 

Const iFlags = 0 

ReDim bArray(1 To maxLength) 
ReDim buf(1 To maxLength) 

dStartTime = Time 
While (Length < maxLength) And (4 > DateDiff("s", dStartTime, Time)) 
    DoEvents 
    count = recv(socketID, buf(1), maxLength, iFlags) 

    If count = SOCKET_ERROR Then '-1 
     nErr = Err.LastDllError() 
     If nErr = 0 Then 
      RecvB = -1 
     Else 
      RecvB = -nErr 
     End If 
     'Debug.Print "socket_error in RecvB. lastdllerror:", nErr 
     Exit Function ' 
    End If ' 
    For i = 1 To count 
     bArray(Length + i) = buf(i) 
    Next 
    Length = Length + count 
Wend 
RecvB = Length 

End Function 

这是TCP代码，而不是电子邮件的代码。它还包括我以前没有发布过的OSX VBA TCP代码。