module1.bas

实际是一个网络编程中模拟读写串口的程序.不过是创建了一个文件,把文件当作串口进行操作

Attribute VB_Name = "Module1"

Public Type SECURITY_ATTRIBUTES
        nLength As Long
        lpSecurityDescriptor As Long
        bInheritHandle As Long
End Type

Type OVERLAPPED
        Internal As Long
        InternalHigh As Long
        offset As Long
        OffsetHigh As Long
        hEvent As Long
End Type


Type DCB
        DCBlength As Long
        BaudRate As Long
        fBitFields As Long 'See Comments in Win32API.Txt
        wReserved As Integer
        XonLim As Integer
        XoffLim As Integer
        ByteSize As Byte
        Parity As Byte
        StopBits As Byte
        XonChar As Byte
        XoffChar As Byte
        ErrorChar As Byte
        EofChar As Byte
        EvtChar As Byte
        wReserved1 As Integer 'Reserved; Do Not Use
End Type

Public Const GENERIC_READ = &H80000000
Public Const GENERIC_WRITE = &H40000000

Public Const FILE_SHARE_READ = &H1
Public Const FILE_SHARE_WRITE = &H2
Public Const INVALID_HANDLE_VALUE = -1
Public Const CREATE_NEW = 1
Public Const CREATE_ALWAYS = 2
Public Const OPEN_ALWAYS = 4
Public Const OPEN_EXISTING = 3
Public Const TRUNCATE_EXISTING = 5

Public Type COMMCONFIG
    dwSize As Long
    wVersion As Integer
    wReserved As Integer
    dcbx As DCB
    dwProviderSubType As Long
    dwProviderOffset As Long
    dwProviderSize As Long
    wcProviderData As Byte
End Type


Public Declare Function PurgeComm Lib "kernel32" (ByVal hFile As Long, ByVal dwFlags As Long) As Long

Public Declare Function GetCommState Lib "kernel32" (ByVal nCid As Long, lpDCB As DCB) As Long


Public Declare Function BuildCommDCB Lib "kernel32" Alias "BuildCommDCBA" (ByVal lpDef As String, lpDCB As DCB) As Long

Public Declare Function CreateFile Lib "kernel32" Alias "CreateFileA" (ByVal lpFileName As String, ByVal dwDesiredAccess As Long, ByVal dwShareMode As Long, lpSecurityAttributes As SECURITY_ATTRIBUTES, ByVal dwCreationDisposition As Long, ByVal dwFlagsAndAttributes As Long, ByVal hTemplateFile As Long) As Long
Public Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long '必要的关闭串口API
Public Declare Function ReadFile Lib "kernel32" (ByVal hFile As Long, lpBuffer As Any, ByVal nNumberOfBytesToRead As Long, lpNumberOfBytesRead As Long, lpOverlapped As OVERLAPPED) As Long
Public Declare Function SetCommState Lib "kernel32" (ByVal hCommDev As Long, lpDCB As DCB) As Long
Public Declare Function WriteFile Lib "kernel32" (ByVal hFile As Long, lpBuffer As Any, ByVal nNumberOfBytesToWrite As Long, lpNumberOfBytesWritten As Long, lpOverlapped As OVERLAPPED) As Long
Public Declare Function SetCommConfig Lib "kernel32" (ByVal hCommDev As Long, lpCC As COMMCONFIG, ByVal dwSize As Long) As Long

Public Declare Function FormatMessage Lib "kernel32" Alias "FormatMessageA" (ByVal dwFlags As Long, lpSource As Any, ByVal dwMessageId As Long, ByVal dwLanguageId As Long, ByVal lpBuffer As String, ByVal nSize As Long, Arguments As Long) As Long
Public Declare Function LocalFree Lib "kernel32" (ByVal hMem As Long) As Long
Public Const FORMAT_MESSAGE_ALLOCATE_BUFFER = &H100
Public Const FORMAT_MESSAGE_FROM_SYSTEM = &H1000
Public Const LANG_NEUTRAL = &H0
Public Const SUBLANG_DEFAULT = &H1                       '  user default

Public Declare Function GetLastError Lib "kernel32" () As Long