VB 进程间通讯

对于进程间的 通讯有N多种方法,常见的有DDE,还有内存文件映射,管道,自定义消息,甚至WINSOCK等等很多种方法本文就内存文件映射来说下进程间的通讯.

建立程序A代码如下

VERSION 5.00
Begin VB.Form Form1
   Caption         =   "Form1"
   ClientHeight    =   3090
   ClientLeft      =   60
   ClientTop       =   450
   ClientWidth     =   4680
   LinkTopic       =   "Form1"
   ScaleHeight     =   3090
   ScaleWidth      =   4680
   StartUpPosition =   3  '窗口缺省
   Begin VB.CommandButton Command1
      Caption         =   "Command1"
      Height          =   555
      Left            =   1170
      TabIndex        =   0
      Top             =   960
      Width           =   1245
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Private Declare Function CreateFileMapping Lib "kernel32" Alias "CreateFileMappingA" (ByVal hFile As Long, lpFileMappigAttributes As Any, ByVal flProtect As Long, ByVal dwMaximumSizeHigh As Long, ByVal dwMaximumSizeLow As Long, ByVal lpName As String) As Long
Private Declare Function MapViewOfFile Lib "kernel32" (ByVal hFileMappingObject As Long, ByVal dwDesiredAccess As Long, ByVal dwFileOffsetHigh As Long, ByVal dwFileOffsetLow As Long, ByVal dwNumberOfBytesToMap As Long) As Long
Private Declare Function UnmapViewOfFile Lib "kernel32" (lpBaseAddress As Any) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
Private Declare Function GetCurrentProcess Lib "kernel32" () As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
Private Declare Function WriteProcessMemory Lib "kernel32" (ByVal hProcess As Long, lpBaseAddress As Any, lpBuffer As Any, ByVal nSize As Long, lpNumberOfBytesWritten As Long) As Long
Private Declare Function ReadProcessMemory Lib "kernel32" (ByVal hProcess As Long, lpBaseAddress As Any, lpBuffer As Any, ByVal nSize As Long, lpNumberOfBytesWritten As Long) As Long

Private Type myType
    hFile As Long
    strTmp(259) As Byte
End Type

Private Sub Command1_Click()
    Dim hMap As Long, pMap As Long, m As myType, j As Long, h As Long, n As myType, bytes(9) As Byte
    hMap = CreateFileMapping(GetCurrentProcess, ByVal 0, 983071, 0, 256, "myTest")
    If hMap <> 0 And hMap <> -1 Then
        m.hFile = 123
        CopyMemory m.strTmp(0), ByVal "123", LenB("123")

        pMap = MapViewOfFile(hMap, 983071, 0, 0, 256)
'       把信息写到共享的地址空间,这里也可以用下面的WriteProcessMemory是一样的道理
        CopyMemory ByVal pMap, m, Len(m)
        If pMap <> 0 Then
'            h = WriteProcessMemory(GetCurrentProcess, ByVal pMap, m, Len(m), j)
'            试着读数据,也可以用CopyMemory
'            h = ReadProcessMemory(GetCurrentProcess, ByVal pMap, n, Len(n), j)
        End If
    End If
End Sub

 

然后再建立程序B源码如下:

VERSION 5.00
Begin VB.Form Form1
   Caption         =   "Form1"
   ClientHeight    =   3090
   ClientLeft      =   60
   ClientTop       =   450
   ClientWidth     =   4680
   LinkTopic       =   "Form1"
   ScaleHeight     =   3090
   ScaleWidth      =   4680
   StartUpPosition =   3  '窗口缺省
   Begin VB.CommandButton Command1
      Caption         =   "Command1"
      Height          =   795
      Left            =   630
      TabIndex        =   0
      Top             =   690
      Width           =   1425
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Private Declare Function CreateFileMapping Lib "kernel32" Alias "CreateFileMappingA" (ByVal hFile As Long, lpFileMappigAttributes As Any, ByVal flProtect As Long, ByVal dwMaximumSizeHigh As Long, ByVal dwMaximumSizeLow As Long, ByVal lpName As String) As Long
Private Declare Function OpenFileMapping Lib "kernel32" Alias "OpenFileMappingA" (ByVal dwDesiredAccess As Long, ByVal bInheritHandle As Long, ByVal lpName As String) As Long
Private Declare Function MapViewOfFile Lib "kernel32" (ByVal hFileMappingObject As Long, ByVal dwDesiredAccess As Long, ByVal dwFileOffsetHigh As Long, ByVal dwFileOffsetLow As Long, ByVal dwNumberOfBytesToMap As Long) As Long
Private Declare Function UnmapViewOfFile Lib "kernel32" (lpBaseAddress As Any) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
Private Declare Function GetCurrentProcess Lib "kernel32" () As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
Private Declare Function ReadProcessMemory Lib "kernel32" (ByVal hProcess As Long, lpBaseAddress As Any, lpBuffer As Any, ByVal nSize As Long, lpNumberOfBytesWritten As Long) As Long
Private Declare Function OpenProcess Lib "kernel32" (ByVal dwDesiredAccess As Long, ByVal bInheritHandle As Long, ByVal dwProcessId As Long) As Long
Private Type myType
    hFile As Long
    strTmp(259) As Byte
End Type

Private Sub Command1_Click()
    Dim hMap As Long, pMap As Long, m As myType, pm As Long
    Dim h As Long
    pm = VarPtr(m)
    hMap = OpenFileMapping983071, 0, "myTest")
    If hMap <> 0 And hMap <> -1 Then
        pMap = MapViewOfFile(hMap, 983071 0, 0, Len(m))
        If pMap <> 0 Then
            CopyMemory m, ByVal pMap, Len(m)

        End If
    End If
End Sub