求ASP版的BASE62加密解密代码

[lovemmc]

网上能找到PHP的，但找不到ASP版的，求个用，谢谢了~~~~

[hookee]

<%

mc_astrB64Alphabet = Array("A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z",_
                     "a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z",_
                     "0","1","2","3","4","5","6","7","8","9","+","/")

Function B64Encode(byval strData)
    dim i,j,a,b,e
    dim A1,A2,A3,A4,B1,B2,B3,B4
    dim lngSurffix
    dim strRet
    lngSurffix=(lenb(strData) mod 3)
    for i=0 to lenb(strData)\3-1
        A1=ascb(midb(strData,i*3+1,1))
        A2=ascb(midb(strData,i*3+2,1))
        A3=ascb(midb(strData,i*3+3,1))
        B1= ((A1 and 252)\04)
        B2=((A1 And 03)*16) or ((A2 and 240)\16)
        B3=((A2 And 15)*04) Or ((A3 And 192)\64)
        B4=((A3 and 63)*01)
        strRet=strRet & mc_astrB64Alphabet(B1) & mc_astrB64Alphabet(B2) & mc_astrB64Alphabet(B3) & mc_astrB64Alphabet(B4)
    next 
    if lngSurffix=1 then 
        A1=ascb(midb(strData,i*3+1,1))
        B1=((A1 and 252)\04)
        B2=((A1 and 03)*16)
        strRet=strRet & mc_astrB64Alphabet(B1) & mc_astrB64Alphabet(B2) & "=="
    elseif lngSurffix=2 Then 
        A1=ascb(midb(strData,i*3+1,1))
        A2=ascb(midb(strData,i*3+2,1))
        B1=((A1 and 252)\04)
        B2=((A1 and 03)*16) or ((A2 and 240)\16)
        B3=((A2 and 15)*04)    
        strRet=strRet & mc_astrB64Alphabet(B1) & mc_astrB64Alphabet(B2) & mc_astrB64Alphabet(B3) & ""=""
    end if 
    B64Encode=strRet
end Function 

Function B64Decode(s)
    Dim oDoc
    Set oDoc = CreateObject("Msxml2.DOMDocument")
    With oDoc
        .loadXml "<root/>"
        .DocumentElement.DataType = "bin.base64"
        .DocumentElement.text = s
        B64Decode = .DocumentElement.NodeTypedValue
    End With
    Set oDoc = Nothing
End Function

a="中文1"
Response.Write B64Decode(B64Encode(a))
%>

[hookee]

简单点:

<%
Function B64Encode(s)
    Dim oDoc, oStream1, oStream2

    Set oStream1 = CreateObject("ADODB.Stream")
    With oStream1
        .Type = 2
        .Mode = 3
        .Open
        .WriteText s
        .Position = 1
    End With
    Set oStream2 = CreateObject("ADODB.Stream")
    With oStream2
        .Type = 1
        .Mode = 3
        .Open
    End With
    oStream1.CopyTo oStream2
    Set oStream1 = Nothing
    oStream2.Position = 1
    Set oDoc = CreateObject("Msxml2.DOMDocument")
    With oDoc
        .loadXml "<root/>"
        .DocumentElement.DataType = "bin.base64"
        .DocumentElement.NodeTypedValue = oStream2.Read(oStream2.size)
        B64Encode = .DocumentElement.text
    End With
    Set oStream2 = Nothing
    Set oDoc = Nothing
End Function

Function B64Decode(s)
    Dim oDoc
    Set oDoc = CreateObject("Msxml2.DOMDocument")
    With oDoc
        .loadXml "<root/>"
        .DocumentElement.DataType = "bin.base64"
        .DocumentElement.text = s
        B64Decode = .DocumentElement.NodeTypedValue
    End With
    Set oDoc = Nothing
End Function

a="1中文"
Response.Write B64Decode(B64Encode(a))
%>

[lovemmc]

上面两个我试了一下，怎么有些字符好像加密后比BASE64的还要长呢?
我是用做网站搜索关键字URL传递参数加密用的，接收页面再解密出来。
有能加密成短点的吗？

[lovemmc]

哦，对了，最好加密后没有 =,/,+ 这种字符，万分感谢~

[hookee]

1. base64是编码而不是加密算法。用于把非Ascii字符转成7位ascii字符来传递，自然是比原字符串长。
2. = / +是base64算法规定的，当然可以用其他字符，不过要自己写算法了,如上面的mc_astrB64Alphabet。
3. 加密算法也不能保证密文比较短。用压缩算法或许可以，但对短字符串的效果不一定好。