字串加解密 - Base64
'加密：base64_encode(str)
'解密：base64_decode(str)
Function base64_encode(DecryptedText)
Dim c1, c2, c3
Dim w1
Dim w2
Dim w3
Dim w4
Dim n
Dim retry
For n = 1 To Len(DecryptedText) Step 3
c1 = Asc(Mid(DecryptedText, n, 1))
c2 = Asc(Mid(DecryptedText, n + 1, 1) + Chr(0))
c3 = Asc(Mid(DecryptedText, n + 2, 1) + Chr(0))
w1 = Int(c1 / 4)
w2 = (c1 And 3) * 16 + Int(c2 / 16)
If Len(DecryptedText) >= n + 1 Then w3 = (c2 And 15) * 4 + Int(c3 / 64) Else w3 = -1
If Len(DecryptedText) >= n + 2 Then w4 = c3 And 63 Else w4 = -1
retry = retry + mimeencode(w1) + mimeencode(w2) + mimeencode(w3) + mimeencode(w4)
Next
base64_encode = retry
End Function
Function base64_decode(a)
Dim w1
Dim w2
Dim w3
Dim w4
Dim n
Dim retry
For n = 1 To Len(a) Step 4
w1 = mimedecode(Mid(a, n, 1))
w2 = mimedecode(Mid(a, n + 1, 1))
w3 = mimedecode(Mid(a, n + 2, 1))
w4 = mimedecode(Mid(a, n + 3, 1))
If w2 >= 0 Then retry = retry + Chr(((w1 * 4 + Int(w2 / 16)) And 255))
If w3 >= 0 Then retry = retry + Chr(((w2 * 16 + Int(w3 / 4)) And 255))
If w4 >= 0 Then retry = retry + Chr(((w3 * 64 + w4) And 255))
Next
base64_decode = retry
End Function
Function mimeencode(w)
If w >= 0 Then mimeencode = Mid(base64, w + 1, 1) Else mimeencode = ""
End Function
Function mimedecode(a)
If Len(a) = 0 Then mimedecode = -1: Exit Function
mimedecode = InStr(base64, a) - 1
End Function
'解密：base64_decode(str)
Function base64_encode(DecryptedText)
FunctionDim c1, c2, c3Dim w1Dim w2Dim w3Dim w4Dim nDim retry For n = 1 To Len(DecryptedText) Step 3 c1 = Asc(Mid(DecryptedText, n, 1)) c2 = Asc(Mid(DecryptedText, n + 1, 1) + Chr(0)) c3 = Asc(Mid(DecryptedText, n + 2, 1) + Chr(0)) w1 = Int(c1 / 4) w2 = (c1 And 3) * 16 + Int(c2 / 16) If Len(DecryptedText) >= n + 1 Then w3 = (c2 And 15) * 4 + Int(c3 / 64) Else w3 = -1 If Len(DecryptedText) >= n + 2 Then w4 = c3 And 63 Else w4 = -1 retry = retry + mimeencode(w1) + mimeencode(w2) + mimeencode(w3) + mimeencode(w4) Next base64_encode = retryEnd Function Function base64_decode(a)
FunctionDim w1Dim w2Dim w3Dim w4Dim nDim retry For n = 1 To Len(a) Step 4 w1 = mimedecode(Mid(a, n, 1)) w2 = mimedecode(Mid(a, n + 1, 1)) w3 = mimedecode(Mid(a, n + 2, 1)) w4 = mimedecode(Mid(a, n + 3, 1)) If w2 >= 0 Then retry = retry + Chr(((w1 * 4 + Int(w2 / 16)) And 255)) If w3 >= 0 Then retry = retry + Chr(((w2 * 16 + Int(w3 / 4)) And 255)) If w4 >= 0 Then retry = retry + Chr(((w3 * 64 + w4) And 255)) Next base64_decode = retryEnd FunctionFunction mimeencode(w) If w >= 0 Then mimeencode = Mid(base64, w + 1, 1) Else mimeencode = ""End FunctionFunction mimedecode(a) If Len(a) = 0 Then mimedecode = -1: Exit Function mimedecode = InStr(base64, a) - 1End Function