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编程10000问
如何编制一个产生随机密码的函数?
如何利用当前时间生成随机函数?
如何做一个密码“生成器”?
如何做一个随机密码产生器?
如何将产生的密码记录并发送给用户并通过点击链接激活?
如何取回已忘记的密码?
如何让用户也能修改密码?
如何在线更改密码?
如何计算出当前日期属于定义时间段内的第几星期?
如何验证日期输入是否正确?
如何制作一个倒计时的程序?
如何制作一个Web日程安排表?
如何在网站中插播广告?
如何拒绝同一张表单被多次提交?
不用Global.asa也能实现统计在线人数吗?
如何防范利用刷新来“作弊”的计数器?
如何防止计数器刷新计数?
如何让计数器只对新进用户计数?
如何实时获知多少人在线?
如何最准确地统计在线用户数?

编程10000问 中的 怎样给文件加密最安全?


出处:互联网   整理: 软晨网(RuanChen.com)   发布: 2010-01-10   浏览: 29 ::
收藏到网摘: n/a

<%@ Language = VBScript%>
<%

Response.Expires = 0


p = "abcdefg"
Set TestPWD = New CPassWord
TestPWD.EnPWD p
TestPWD.UnPWD TestPWD.ShowPWD(True)
k = TestPWD.ShowPWD(True)
l = TestPWD.ShowPWD(False)
Set TestPWD = Nothing
With Response
.Write "
原文:" & p & "<br>"
.Write "
加密后:" & k & "<br>"
.Write "
解密后:" & L & "<br>"
End With

Class CPassWord
Private CEnPWD,CUnPWD
Private Function My_Hex(My_Hex_Source)
My_Hex = Hex(My_Hex_Source)
If Len(My_Hex) = 1 Then
My_Hex = "0" & My_Hex
End If
End Function
Private Function My_UnHex(My_UnHex_Source)
If Len(My_UnHex_Source) = 2 Then
Temp_Value = My_HexReplace(Left(My_UnHex_Source,1))
End If
My_UnHex = Temp_Value * 16 + My_HexReplace(Right(My_UnHex_Source,1))
End Function
Private Function My_HexReplace(My_HexReplace_Source)
If Asc(My_HexReplace_Source) > 64 Then
My_HexReplace = Asc(UCase(My_HexReplace_Source)) - 55
Else
My_HexReplace = Asc(My_HexReplace_Source) - 48
End If
End Function
Public Property Get ShowPWD(EnP)

' 输出.
If EnP Then
ShowPWD = CEnPWD
Else
ShowPWD = CUnPWD
End If
End Property
Sub EnPWD(EnPWD_Source)
if EnPWD_Source = "" then
CEnPWD = 0
Exit Sub
else
Randomize
Key = Rnd * 256
While Key = 0
Key = Rnd * 256
Wend
For i=1 To Len(EnPWD_Source)
Temp_String = Key Xor Asc(Mid(EnPWD_Source,i,1))
Crc = Crc + Temp_String
CEnPWD = CEnPWD + My_Hex(Temp_String)
Next
CEnPWD = My_Hex(Key) + StrReverse(CEnPWD) + My_Hex(Crc Mod 256)
End if
End Sub
Sub UnPWD(UnPWD_Source)
If Len(UnPWD_Source) < 6 Or Len(UnPWD_Source) Mod 2 = 1 then
CUnPWD = 0
Exit Sub
End If
Old_Key = My_UnHex(Left(UnPWD_Source,2))
Old_Crc = My_UnHex(Right(UnPWD_Source,2))
Old_String = StrReverse(Mid(UnPWD_Source,3,Len(UnPWD_Source)-4))
For i=1 To Len(Old_String) - 1 Step 2
Temp_Value = My_UnHex(Mid(Old_String,i,2))
Crc_Temp = Crc_Temp + Temp_Value
Temp_String = Temp_String + Chr(Temp_Value Xor Old_Key)
Next
If Old_Crc <> (Crc_Temp Mod 256) Then
CUnPWD = 403
Exit Sub
End If
CUnPWD = Temp_String
End Sub
End Class

%>