I am looking for a simple way to encode an inputted text into Rot13. I am hitting a brick wall at the stage of being able to separate out words into individual characters and in
It seems like you're making this way harder than it has to be. No need to separate words, etc, and definitely no need for a large If/Else block:
Public Function Rot13(ByVal input As String) As String
Dim result As Char() = input.ToCharArray()
For i As Integer = 0 To result.Length - 1
Dim temp As Integer = Asc(result(i))
Select Case temp
Case 65 to 77, 97 To 109 'A - M
result(i) = Chr(temp + 13)
Case 78 to 90, 110 To 122 'N - Z
result(i) = Chr(temp - 13)
End Select
Next i
Return New String(result)
End Function
Note that this was entered directly into the browser window and is completely untested.