Codigo Visual Basic

Dim UserKeyX As String

Dim Temp As Integer

Dim Times As Integer

Dim i As Integer

Dim j As Integer

Dim n As Integer

Dim rtn As String

'//Get UserKey characters

n = Len(UserKey)

ReDim UserKeyASCIIS(1 To n)

For i = 1 To n

UserKeyASCIIS(i) = Asc(Mid$(UserKey, i, 1))

Next

'//Get Text characters

ReDim TextASCIIS(Len(Text)) As Integer

For i = 1 To Len(Text)

TextASCIIS(i) = Asc(Mid$(Text, i, 1))

Next

'//Encryption/Decryption

If Action = ENCRYPT Then

For i = 1 To Len(Text)

j = IIf(j + 1 >= n, 1, j + 1)

Temp = TextASCIIS(i) + UserKeyASCIIS(j)

If Temp > 255 Then

Temp = Temp - 255

End If

rtn = rtn + Chr$(Temp)

Next

ElseIf Action = DECRYPT Then

For i = 1 To Len(Text)

j = IIf(j + 1 >= n, 1, j + 1)

Temp = TextASCIIS(i) - UserKeyASCIIS(j)

If Temp < 0 Then

Temp = Temp + 255

End If

rtn = rtn + Chr$(Temp)

Next

End If

'//Return

EncryptString = rtn

End Function

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