excel - 如何在 VBA 中将 FILETIME 转换为日期？

Question

我正在尝试编写一个模块，该模块将从注册表项中提取十六进制文件时间并将其解析为 VBA 中的可读日期。

我从注册表中提取了以下 REG_BINARY key : 36 D0 56 2E 14 52 D5 01 00 60 EE 78 DE FF FF FF C4 00 8E 01 FF FF FF 7F

到目前为止，我有以下函数来尝试转换它:

Public Sub ConvertHex2Date()
    Dim lbyte, ubyte, convByteL, convByteU As Long
    Dim FT As FileTime
    Dim SysTimeDate As Date
    Dim bArrL() As Byte
    Dim bArrU() As Byte
    convByteL = 3577643008# 'Lower Byte Conversion Factor
    convByteU = 27111902    'Upper Byte COnversion Factor

    Dim str, strlByte, struByte As String

    str = "36 D0 56 2E 14 52 D5 01 00 60 EE 78 DE FF FF FF C4 00 8E 01 FF FF FF 7F "
    str = Left(Replace(Trim(str), " ", ""), 16)

    strlByte = Left(str, 8) 'Hex String Lower Byte
    struByte = Right(str, 8) 'Hex String Upper Byte

    bArrL = Hex2ByteArr(strlByte)
    bArrU = Hex2ByteArr(struByte)

    lbyte = ByteArr2Long(bArrL)
    ubyte = ByteArr2Long(bArrU)

    FT.dwLowDateTime = lbyte
    FT.dwHighDateTime = ubyte
    SysTimeDate = FileTimeToSerialTime(FT)
End Sub

关联辅助子:

Private Const FORMAT_MESSAGE_TEXT_LEN = &HA0 ' from ERRORS.H C++ include file.
Private Const FORMAT_MESSAGE_FROM_STRING = &H400
Private Const FORMAT_MESSAGE_FROM_SYSTEM = &H1000
Private Const FORMAT_MESSAGE_IGNORE_INSERTS = &H200

'''''''''''''''''''''''''''''''''''''''
' Windows API Functions
'''''''''''''''''''''''''''''''''''''''
Private 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 Type FileTime
    dwLowDateTime As Long
    dwHighDateTime As Long
End Type

Public Type SYSTEMTIME
    wYear As Integer
    wMonth As Integer
    wDayOfWeek As Integer
    wDay As Integer
    wHour As Integer
    wMinute As Integer
    wSecond As Integer
    wMilliseconds As Integer
End Type

Private Declare Function FileTimeToSystemTime Lib "kernel32" ( _
    lpFileTime As FileTime, _
    lpSystemTime As SYSTEMTIME) As Long


Public Sub ConvertHex2Date()
    Dim lbyte, ubyte, convByteL, convByteU As Long
    Dim FT As FileTime
    Dim SysTimeDate As Date
    Dim bArrL() As Byte
    Dim bArrU() As Byte
    convByteL = 3577643008# 'Lower Byte Conversion Factor
    convByteU = 27111902    'Upper Byte COnversion Factor

    Dim str, strlByte, struByte As String

    str = "36 D0 56 2E 14 52 D5 01 00 60 EE 78 DE FF FF FF C4 00 8E 01 FF FF FF 7F "
    str = Left(Replace(Trim(str), " ", ""), 16)

    strlByte = Left(str, 8) 'Hex String Lower Byte
    struByte = Right(str, 8) 'Hex String Upper Byte

    bArrL = Hex2ByteArr(strlByte)
    bArrU = Hex2ByteArr(struByte)

    lbyte = ByteArr2Long(bArrL)
    ubyte = ByteArr2Long(bArrU)

    FT.dwLowDateTime = lbyte
    FT.dwHighDateTime = ubyte
    SysTimeDate = FileTimeToSerialTime(FT)
End Sub

Public Function FileTimeToSerialTime(FileTimeValue As FileTime) As Date
    '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    ' FileTimeToSerialTime
    ' This function converts a FILETIME to a Double Serial DateTime.
    ' TESTED
    '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    Dim SysTime As SYSTEMTIME
    Dim Res As Long
    Dim ErrNum As Long
    Dim ErrText As String
    Dim ResultDate As Date

    '''''''''''''''''''''''''''''''''''''''''''''''''''''''
    ' Convert FileTimeValue FILETIME to SysTime SYSTEMTIME.
    '''''''''''''''''''''''''''''''''''''''''''''''''''''''
    Res = FileTimeToSystemTime(lpFileTime:=FileTimeValue, lpSystemTime:=SysTime)
    If Res = 0 Then
        '''''''''''''''''''''
        ' An error occurred
        '''''''''''''''''''''
        ErrNum = Err.LastDllError
        ErrText = GetSystemErrorMessageText(ErrNum)
        Debug.Print "Error With FileTimeToSystemTime:" & vbCrLf & _
                    "Err:  " & CStr(ErrNum) & vbCrLf & _
                    "Desc: " & ErrText
        FileTimeToSerialTime = False
        Exit Function
    End If

    With SysTime
        ResultDate = DateSerial(.wYear, .wMonth, .wDay) + _
                    TimeSerial(.wHour, .wMinute, .wSecond)
        MsgBox (ResultDate)
    End With

    FileTimeToSerialTime = ResultDate
End Function

Public Function Hex2ByteArr(ByVal sHex As String) As Byte()
    Dim n As Long
    Dim nCount As Long
    Dim bArr() As Byte
    nCount = Len(sHex)
    If (nCount And 1) = 1 Then
        sHex = "0" & sHex
        nCount = nCount + 1
    End If
    ReDim bArr(nCount \ 2 - 1)
    For n = 1 To nCount Step 2
        bArr((n - 1) \ 2) = CByte("&H" & Mid$(sHex, n, 2))
    Next
    Hex2ByteArr = bArr
End Function

Public Function ByteArr2Long(ArrByte() As Byte) As Long
    Dim myLong, I As Long
    For I = 0 To UBound(ArrByte)
        myLong = myLong + ArrByte(I) * (256 ^ (UBound(ArrByte) - I))
    Next I

    ByteArr2Long = myLong
End Function

Public Function GetSystemErrorMessageText(ErrorNumber As Long) As String
    Dim ErrorText As String
    Dim TextLen As Long
    Dim FormatMessageResult As Long
    Dim LangID As Long

    ' initialize the variables
    LangID = 0&  'default language
    ErrorText = String$(FORMAT_MESSAGE_TEXT_LEN, vbNullChar)
    TextLen = Len(ErrorText)
    On Error Resume Next
    FormatMessageResult = FormatMessage( _
                    dwFlags:=FORMAT_MESSAGE_FROM_SYSTEM Or _
                             FORMAT_MESSAGE_IGNORE_INSERTS, _
                    lpSource:=0&, _
                    dwMessageId:=ErrorNumber, _
                    dwLanguageId:=0&, _
                    lpBuffer:=ErrorText, _
                    nSize:=TextLen, _
                    Arguments:=0&)
    On Error GoTo 0
    If FormatMessageResult = 0& Then
        MsgBox "An error occurred with the FormatMessage" & _
            " API functiopn call. Error: " & _
            CStr(Err.LastDllError) & _
            " Hex(" & Hex(Err.LastDllError) & ")."
        GetSystemErrorMessageText = vbNullString
        Exit Function
    End If
    If FormatMessageResult > 0 Then
        ErrorText = Left$(ErrorText, FormatMessageResult)
        GetSystemErrorMessageText = ErrorText
    Else
        GetSystemErrorMessageText = "NO ERROR DESCRIPTION AVAILABLE"
    End If
End Function

有人可以帮我找出从 FILETIME 转换为常规系统时间时我做错了什么吗？

如果您将此宏复制到 Excel 并运行它，它会显示日期 9/17/6241 和一些更改。该日期实际上应该是 2019 年 8 月 12 日至 8 月 15 日左右(没有确切的值)。这是怎么回事？

我正在查看的确切注册表项位于: 计算机\HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\PowerPoint\Security\Trusted Documents\TrustRecords

显然其他人已经成功地将前 2 个字节转换为日期: https://brettshavers.com/brett-s-blog/entry/regripper

但是，他们的函数是用 Perl 编写的，我不太明白。

#-------------------------------------------------------------
# getTime()
# Translate FILETIME object (2 DWORDS) to Unix time, to be passed
# to gmtime() or localtime()
#-------------------------------------------------------------
sub getTime($$) {
  my $lo = shift;
  my $hi = shift;
  my $t;

  if ($lo == 0 && $hi == 0) {
    $t = 0;
  } else {
    $lo -= 0xd53e8000;
    $hi -= 0x019db1de;
    $t = int($hi*429.4967296 + $lo/1e7);
  };
  $t = 0 if ($t < 0);
  return $t;
}

更多资源:http://www.cpearson.com/excel/FileTimes.htm

https://learn.microsoft.com/en-us/windows/win32/api/minwinbase/ns-minwinbase-filetime

Answer 1

像这样恢复十六进制字符串的前两个字节

str = "36 D0 56 2E 14 52 D5 01 00 60 EE 78 DE FF FF FF C4 00 8E 01 FF FF FF 7F "
str = Left(Replace(Trim(str), " ", ""), 16)
str = Mid(str, 7, 2) & Mid(str, 5, 2) & Mid(str, 3, 2) & Mid(str, 1, 2) & _
      Mid(str, 15, 2) & Mid(str, 13, 2) & Mid(str, 11, 2) & Mid(str, 9, 2)

结果str将类似于str = "2E 56 D0 36 01 D5 52 14"，最终结果将是结果:1​​3-08-2019 20:17:50 信用 Link和 Link 。然而 谢谢，我学到了很多为什么要测试和研究