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VBScript code

Sub Main()
    Dim hdlSRCFile As Long
    Dim NowsStart As Currency
    Dim lMoveLo As Long, lMoveHi As Long
    ...
    NowsStart = 3146959360@ '假定这是你要定位的位置
    Size2Long NowsStart, lMoveLo, lMoveHi '用你7楼的函数转换
    
    SetFilePointer hdlSRCFile, lMoveLo, lMoveHi, FILE_BEGIN
End Sub

VB.NET code

'货币类型转换为大整数结构
Public Function Currency2LargeInteger(ByVal curDistance As Currency) As LARGE_INTEGER
    CopyMemory Currency2LargeInteger, curDistance, 8
End Function
'大整数结构转换为货币类型
Public Function LargeInteger2Currency(li As LARGE_INTEGER) As Currency
    CopyMemory LargeInteger2Currency, li, 8
End Function

VB.NET code

Public Function MySeek(ByVal hFile As Long, ByVal curDistance As Currency, ByVal lMoveMethod As Long) As Currency
    Dim li As LARGE_INTEGER
    li = Currency2LargeInteger(curDistance)
    li.lowpart = SetFilePointer(hFile, li.lowpart, li.highpart, lMoveMethod)
    
    If li.lowpart = -1 Or Err.LastDllError <> 0 Then
        li = Currency2LargeInteger(-1@)
    End If
    
    MySeek = LargeInteger2Currency(li)
    
    Debug.Print "Seek to "; Hex(li.highpart); Hex(li.lowpart)
End Function

VB.NET code

Option Explicit
Public Const MOVEFILE_REPLACE_EXISTING = &H1
Public Const FILE_ATTRIBUTE_TEMPORARY = &H100
Public Const FILE_BEGIN = 0
Public Const FILE_SHARE_READ = &H1
Public Const FILE_SHARE_WRITE = &H2
Public Const CREATE_NEW = 1
Public Const OPEN_EXISTING = 3
Public Const GENERIC_READ = &H80000000
Public Const GENERIC_WRITE = &H40000000

Public Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
Public Declare Function WriteFile Lib "kernel32" (ByVal hFile As Long, lpBuffer As Any, ByVal nNumberOfBytesToWrite As Long, lpNumberOfBytesWritten As Long, ByVal lpOverlapped As Any) As Long
Public Declare Function ReadFile Lib "kernel32" (ByVal hFile As Long, lpBuffer As Any, ByVal nNumberOfBytesToRead As Long, lpNumberOfBytesRead As Long, lpOverlapped As Any) As Long
Public Declare Function CreateFile Lib "kernel32" Alias "CreateFileA" (ByVal lpFileName As String, ByVal dwDesiredAccess As Long, ByVal dwShareMode As Long, ByVal lpSecurityAttributes As Any, 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
Public Declare Function SetFilePointer Lib "kernel32" (ByVal hFile As Long, ByVal lDistanceToMove As Long, lpDistanceToMoveHigh As Long, ByVal dwMoveMethod As Long) As Long
Public Declare Function GetFileSize Lib "kernel32" (ByVal hFile As Long, lpFileSizeHigh As Long) As Long
Public Declare Function SetEndOfFile Lib "kernel32" (ByVal hFile As Long) As Long


' 32 bit
'signed int
'1000 0000 0000 0000 0000 0000 0000 0000
'   =
'8000 0000 -> -2147483648
'
'0111 1111 1111 1111 1111 1111 1111 1111
'   =
'7FFF FFFF -> 0 ~ 2^31-1 2147483647
'
'unsigned int
'1111 1111 1111 1111 1111 1111 1111 1111
'   =
'FFFF FFFF -> 0 ~ 2^32-1 4294967295
'
' 64 bit
'signed int
'1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
'   =
'8000 0000 0000 0000 -> -9223372036854775808
'
'0111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111
'   =
'7FFF FFFF FFFF FFFF -> 0 ~ 2^63-1 9223372036854775807
'                      VB Currency 922337203685477.5807
'
'unsigned int
'1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111
'   =
'FFFF FFFF FFFF FFFF -> 0 ~ 2^64-1 18446744073709551615
Public Type LARGE_INTEGER
    lowpart As Long
    highpart As Long
End Type

Public Function Currency2LargeInteger(ByVal curDistance As Currency) As LARGE_INTEGER
    CopyMemory Currency2LargeInteger, curDistance, 8
End Function

Public Function LargeInteger2Currency(li As LARGE_INTEGER) As Currency
    CopyMemory LargeInteger2Currency, li, 8
End Function

Public Function MyOpen(ByVal sFileName As String) As Long
    MyOpen = CreateFile(sFileName, GENERIC_READ Or GENERIC_WRITE, FILE_SHARE_READ Or FILE_SHARE_WRITE, 0&, OPEN_EXISTING, 0, 0)
End Function

Public Function MySeek(ByVal hFile As Long, ByVal curDistance As Currency, ByVal lMoveMethod As Long) As Currency
    Dim li As LARGE_INTEGER
    li = Currency2LargeInteger(curDistance)
    li.lowpart = SetFilePointer(hFile, li.lowpart, li.highpart, lMoveMethod)
    
    If li.lowpart = -1 Or Err.LastDllError <> 0 Then
        li = Currency2LargeInteger(-1@)
    End If
    
    MySeek = LargeInteger2Currency(li)
    
    Debug.Print "Seek to "; Hex(li.highpart); Hex(li.lowpart)
End Function

VB.NET code

Option Explicit
Private Sub Command1_Click()
    Dim hFile As Long
    hFile = MyOpen("c:\pagefile2.sys")
    If hFile Then
        Dim curPos As Currency
        curPos = 2451374078@
        Debug.Print MySeek(hFile, curPos / 10000@, FILE_BEGIN)
        
        Dim b As Byte, lBytesRead As Long
        ReadFile hFile, b, 1, lBytesRead, ByVal 0
        Debug.Print b
        CloseHandle hFile
    End If
End Sub