C# Signature:

[DllImport("kernel32.dll", SetLastError = true)]
static extern IntPtr MapViewOfFile(IntPtr hFileMappingObject, uint
   dwDesiredAccess, uint dwFileOffsetHigh, uint dwFileOffsetLow,
   uint dwNumberOfBytesToMap);

VB .Net

Declare Function MapViewOfFile Lib "kernel32" (ByVal hFileMappingObject As IntPtr, ByVal dwDesiredAccess As UInt32, ByVal dwFileOffsetHigh As UInt32, ByVal dwFileOffsetLow As UInt32, ByVal dwNumberOfBytesToMap As UInt32) As UInt32

VB .Net Sample Code:

Declare Function MapViewOfFile Lib "kernel32" (ByVal hFileMappingObject As IntPtr, ByVal dwDesiredAccess As UInt32, ByVal dwFileOffsetHigh As UInt32, ByVal dwFileOffsetLow As UInt32, ByVal dwNumberOfBytesToMap As UInt32) As UInt32

Public Structure SECURITY_ATTRIBUTES

    Public lLength As Long
    Public lSecurityDescriptor As Long
    Public lInhertitHandle As Long

End Structure

Dim SecAttrib As SECURITY_ATTRIBUTES

Dim nAckEvent As Integer

Dim nReadyEvent As Integer

Dim nSharedFile As Long

Dim nSharedMem As Long

Dim nSecurityDesc As Integer

Public Const GPTR As Long = &H40

Public Const SECURITY_DESCRIPTOR_REVISION As Long = (1)

Public Const SECURITY_DESCRIPTOR_MIN_LENGTH As Long = (20)

Public Const PAGE_READWRITE As Int32 = &H4

Public Const FILE_MAP_READ As Int32 = &H40&, 512)

nSecurityDesc = GlobalAlloc(GPTR, SECURITY_DESCRIPTOR_MIN_LENGTH)

SecAttrib.lLength = SecAttrib.nLength

SecAttrib.lInheritHandle = Convert.ToInt32(True)

SecAttrib.lSecurityDescriptor = pSecurityDesc

nAckEvent = CreateEvent(SecAttrib, 0, 0, "DBWIN_BUFFER_READY")

nReadyEvent = CreateEvent(SecAttrib, 0, 0, "DBWIN_DATA_READY")

nSharedFile = CreateFileMapping(-1, SecAttrib, PAGE_READWRITE, 0&, 4096, "DBWIN_BUFFER")

nSharedMem = MapViewOfFile(nSharedFile, FILE_MAP_READ, 0&, 0&, 0&, 512)

User-Defined Types:

None.

Notes:

None.

Tips & Tricks:

Please add some!

C# Sample Code:

        const UInt32 STANDARD_RIGHTS_REQUIRED = 0x000F0000;
        const UInt32 SECTION_QUERY = 0x0001;
        const UInt32 SECTION_MAP_WRITE = 0x0002;
        const UInt32 SECTION_MAP_READ = 0x0004;
        const UInt32 SECTION_MAP_EXECUTE = 0x0008;
        const UInt32 SECTION_EXTEND_SIZE = 0x0010;
        const UInt32 SECTION_ALL_ACCESS = (STANDARD_RIGHTS_REQUIRED|SECTION_QUERY|
            SECTION_MAP_WRITE |      
            SECTION_MAP_READ |      
            SECTION_MAP_EXECUTE |    
            SECTION_EXTEND_SIZE);
        const UInt32 FILE_MAP_ALL_ACCESS = SECTION_ALL_ACCESS;
        private IntPtr hHandle;
        private IntPtr pBuffer;
        unsafe public void Attach(string SharedMemoryName, UInt32 NumBytes)
        {
            if (IntPtr.Zero != hHandle) return;
            hHandle = OpenFileMapping(FILE_MAP_ALL_ACCESS, false, SharedMemoryName);
            if (IntPtr.Zero == hHandle) return;
            pBuffer = MapViewOfFile(hHandle, FILE_MAP_ALL_ACCESS, 0, 0, &NumBytes);
        }
        public void Detach()
        {
            if (IntPtr.Zero != hHandle)
            {
                CloseHandle(hHandle); //fair to leak if can't close
                hHandle = IntPtr.Zero;
            }
            pBuffer = IntPtr.Zero;
            lBufferSize = 0;
        }

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