有个MD5的类在检测文件时比较慢懂这方面的高手帮修改下
如果ByteBuffer值能大些比如65535这样速度就快多了。但是发现如果这样MD5值就不唯一了。我也试着修改了下还是不行。只有请研究这方面高手修改下。
Option Explicit
Private Const OFFSET_4 = 4294967296#
Private Const MAXINT_4 = 2147483647
Private State(4) As Long
Private ByteCounter As Long
Private ByteBuffer(63) As Byte
Private Const S11 = 7
Private Const S12 = 12
Private Const S13 = 17
Private Const S14 = 22
Private Const S21 = 5
Private Const S22 = 9
Private Const S23 = 14
Private Const S24 = 20
Private Const S31 = 4
Private Const S32 = 11
Private Const S33 = 16
Private Const S34 = 23
Private Const S41 = 6
Private Const S42 = 10
Private Const S43 = 15
Private Const S44 = 21
Property Get RegisterA() As String
RegisterA = State(1)
End Property
Property Get RegisterB() As String
RegisterB = State(2)
End Property
Property Get RegisterC() As String
RegisterC = State(3)
End Property
Property Get RegisterD() As String
RegisterD = State(4)
End Property
Public Function Md5_String_Calc(SourceString As String) As String
MD5Init
MD5Update LenB(StrConv(SourceString, vbFromUnicode)), StringToArray(SourceString)
MD5Final
Md5_String_Calc = GetValues
End Function
Public Function Md5_File_Calc(InFile As String) As String
On Error GoTo errorhandler
Dim FileO As Integer
FileO = FreeFile
Call FileLen(InFile)
Open InFile For Binary Access Read As #FileO
MD5Init
Do While Not EOF(FileO)
DoEvents
Get #FileO, , ByteBuffer
If Loc(FileO) < LOF(FileO) Then
ByteCounter = ByteCounter + 64
MD5Transform ByteBuffer
End If
Loop
ByteCounter = ByteCounter + (LOF(FileO) Mod 64)
Close #FileO
MD5Final
Md5_File_Calc = GetValues
Exit Function
errorhandler:
Md5_File_Calc = " "
End Function
Private Function StringToArray(InString As String) As Byte()
Dim I As Integer, bytBuffer() As Byte
ReDim bytBuffer(LenB(StrConv(InString, vbFromUnicode)))
bytBuffer = StrConv(InString, vbFromUnicode)
StringToArray = bytBuffer
End Function
Public Function GetValues() As String
GetValues = LongToString(State(1)) & LongToString(State(2)) & LongToString(State(3)) & LongToString(State(4))
End Function
Private Function LongToString(Num As Long) As String
Dim A As Byte, B As Byte, C As Byte, D As Byte
A = Num And &HFF&
If A < 16 Then LongToString = "0 " & Hex(A) Else LongToString = Hex(A)
B = (Num And &HFF00&) \ 256
If B < 16 Then LongToString = LongToString & "0 " & Hex(B) Else LongToString = LongToString & Hex(B)
C = (Num And &HFF0000) \ 65536
If C < 16 Then LongToString = LongToString & "0 " & Hex(C) Else LongToString = LongToString & Hex(C)
If Num < 0 Then D = ((Num And &H7F000000) \ 16777216) Or &H80& Else D = (Num And &HFF000000) \ 16777216
If D < 16 Then LongToString = LongToString & "0 " & Hex(D) Else LongToString = LongToString & Hex(D)
End Function
Public Sub MD5Init()
ByteCounter = 0
State(1) = UnsignedToLong(1732584193#)
State(2) = UnsignedToLong(4023233417#)
State(3) = UnsignedToLong(2562383102#)
State(4) = UnsignedToLong(271733878#)
End Sub
Public Sub MD5Final()
Dim dblBits As Double, padding(72) As Byte, lngBytesBuffered As Long
padding(0) = &H80
dblBits = ByteCounter * 8
lngBytesBuffered = ByteCounter Mod 64
If lngBytesBuffered <= 56 Then MD5Update 56 - lngBytesBuffered, padding Else MD5Update 120 - ByteCounter, padding
padding(0) = UnsignedToLong(dblBits) And &HFF&
padding(1) = UnsignedToLong(dblBits) \ 256 And &HFF&
padding(2) = UnsignedToLong(dblBits) \ 65536 And &HFF&
padding(3) = UnsignedToLong(dblBits) \ 16777216 And &HFF&
padding(4) = 0
padding(5) = 0
padding(6) = 0
padding(7) = 0
MD5Update 8, padding
End Sub
Public Sub MD5Update(InputLen As Long, InputBuffer() As Byte)
Dim II As Integer, I As Integer, J As Integer, K As Integer, lngBufferedBytes As Long, lngBufferRemaining As Long, lngRem As Long
lngBufferedBytes = ByteCounter Mod 64
lngBufferRemaining = 64 - lngBufferedBytes
ByteCounter = ByteCounter + InputLen
If InputLen > = lngBufferRemaining Then
For II = 0 To lngBufferRemaining - 1
ByteBuffer(lngBufferedBytes + II) = InputBuffer(II)
Next II
MD5Transform ByteBuffer
lngRem = (InputLen) Mod 64
For I = lngBufferRemaining To InputLen - II - lngRem Step 64
For J = 0 To 63
ByteBuffer(J) = InputBuffer(I + J)
Next J
MD5Transform ByteBuffer
Next I
lngBufferedBytes = 0
Else
I = 0
End If
For K = 0 To InputLen - I - 1
ByteBuffer(lngBufferedBytes + K) = InputBuffer(I + K)
Next K
End Sub
[解决办法]
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[解决办法]
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