September Morn Update

Task/Caesar-cipher/Visual-Basic-.NET/caesar-cipher.visual

@@ -0,0 +1,31 @@
+Module Module1
+
+    Function Encrypt(ch As Char, code As Integer) As Char
+        If Not Char.IsLetter(ch) Then
+            Return ch
+        End If
+
+        Dim offset = AscW(If(Char.IsUpper(ch), "A"c, "a"c))
+        Dim test = (AscW(ch) + code - offset) Mod 26 + offset
+        Return ChrW(test)
+    End Function
+
+    Function Encrypt(input As String, code As Integer) As String
+        Return New String(input.Select(Function(ch) Encrypt(ch, code)).ToArray())
+    End Function
+
+    Function Decrypt(input As String, code As Integer) As String
+        Return Encrypt(input, 26 - code)
+    End Function
+
+    Sub Main()
+        Dim str = "Pack my box with five dozen liquor jugs."
+
+        Console.WriteLine(str)
+        str = Encrypt(str, 5)
+        Console.WriteLine("Encrypted: {0}", str)
+        str = Decrypt(str, 5)
+        Console.WriteLine("Decrypted: {0}", str)
+    End Sub
+
+End Module