by Bryan Hurley (1 Submission)
Category: Encryption
Compatability: Visual Basic 3.0
Difficulty: Unknown Difficulty
Date Added: Wed 3rd February 2021
Rating: 
(38 Votes)
This simple encryption Function uses Xor encryption and itterative encoding to more securely encrypt a text string. Although the code is not unbreakable, it cannot be broken with a simple key. Itterative encoding ensures that code-cracking techniques, like character frequency study, will not work. It's as easy as could be. Function can be easily modified to encode more than strings.
Inputs
data As String, seed As Long Integer
Assumes
Module is set to Option Base 1. This is to simplify the code. If you are adding this to a pre-existing module, make sure that Base Option 1 will not adversely affect your other functions, or modify the code to work off of Base Option 0.
Code Returns
Function returns String of encoded/decoded text.
VBcodersPublic Function encryptAll(data As String, seed As Long) As String
Dim x As Integer, tmp As String, stepnum As Integer
Dim byteArray() As Byte, seedOffset As Integer, n As String
tmp = Trim$(Str(seed))
seed = 0
For x = 1 To Len(tmp)
n = Mid(tmp, x, 1)
seed = seed + CLng(n)
Next x
reCheckSeed:
If seed > 255 Then
seed = -1 + (seed - 255)
GoTo reCheckSeed
End If
For x = 1 To Len(data)
ReDim Preserve byteArray(x)
n = Mid(data, x, 1)
byteArray(x) = Asc(n)
stepnum = seed + x
reCheckstepnum:
If stepnum > 255 Then
stepnum = -1 + (stepnum - 255)
GoTo reCheckstepnum
End If
byteArray(x) = byteArray(x) Xor CByte(stepnum)
Next x
tmp = ""
For x = 1 To Len(data)
tmp = tmp & Chr(byteArray(x))
Next x
encryptAll = tmp
End Function
