Aes encryption and decryption sample in MSDN Library

[EDN Admin]

I have tried to use the MSDN Library sample about AES class. I created a new console application an copied the sample code and I added:
Console.ReadLine()
to all me read the text but I found that the text before encryption is the same after encryption. What I am doing wrong?Imports System
Imports System.IO
Imports System.Security.Cryptography



Class AesExample

Public Shared Sub Main()
Try

Dim original As String = "Here is some data to encrypt!"

Create a new instance of the Aes
class. This generates a new key and initialization
vector (IV).
Using myAes As Aes = Aes.Create()


Encrypt the string to an array of bytes.
Dim encrypted As Byte() = EncryptStringToBytes_Aes(original, myAes.Key, myAes.IV)

Decrypt the bytes to a string.
Dim roundtrip As String = DecryptStringFromBytes_Aes(encrypted, myAes.Key, myAes.IV)

Display the original data and the decrypted data.
Console.WriteLine("Original: {0}", original)
Console.WriteLine("Round Trip: {0}", roundtrip)
Console.ReadLine()
End Using
Catch e As Exception
Console.WriteLine("Error: {0}", e.Message)
Console.ReadLine()
End Try

End Sub Main

Shared Function EncryptStringToBytes_Aes(ByVal plainText As String, ByVal Key() As Byte, ByVal IV() As Byte) As Byte()
Check arguments.
If plainText Is Nothing OrElse plainText.Length <= 0 Then
Throw New ArgumentNullException("plainText")
End If
If Key Is Nothing OrElse Key.Length <= 0 Then
Throw New ArgumentNullException("Key")
End If
If IV Is Nothing OrElse IV.Length <= 0 Then
Throw New ArgumentNullException("Key")
End If
Dim encrypted() As Byte
Create an Aes object
with the specified key and IV.
Using aesAlg As Aes = Aes.Create()

aesAlg.Key = System.Text.Encoding.UTF8.GetBytes("2")




aesAlg.IV = System.Text.Encoding.UTF8.GetBytes("1")





Create a decrytor to perform the stream transform.
Dim encryptor As ICryptoTransform = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV)
Create the streams used for encryption.
Using msEncrypt As New MemoryStream()
Using csEncrypt As New CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write)
Using swEncrypt As New StreamWriter(csEncrypt)

Write all data to the stream.
swEncrypt.Write(plainText)
End Using
encrypted = msEncrypt.ToArray()
End Using
End Using
End Using

Return the encrypted bytes from the memory stream.
Return encrypted

End Function EncryptStringToBytes_Aes

Shared Function DecryptStringFromBytes_Aes(ByVal cipherText() As Byte, ByVal Key() As Byte, ByVal IV() As Byte) As String
Check arguments.
If cipherText Is Nothing OrElse cipherText.Length <= 0 Then
Throw New ArgumentNullException("cipherText")
End If
If Key Is Nothing OrElse Key.Length <= 0 Then
Throw New ArgumentNullException("Key")
End If
If IV Is Nothing OrElse IV.Length <= 0 Then
Throw New ArgumentNullException("Key")
End If
Declare the string used to hold
the decrypted text.
Dim plaintext As String = Nothing

Create an Aes object
with the specified key and IV.
Using aesAlg As Aes = Aes.Create()
aesAlg.Key = Key
aesAlg.IV = IV

Create a decrytor to perform the stream transform.
Dim decryptor As ICryptoTransform = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV)

Create the streams used for decryption.
Using msDecrypt As New MemoryStream(cipherText)

Using csDecrypt As New CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read)

Using srDecrypt As New StreamReader(csDecrypt)


Read the decrypted bytes from the decrypting stream
and place them in a string.
plaintext = srDecrypt.ReadToEnd()
End Using
End Using
End Using
End Using

Return plaintext

End Function DecryptStringFromBytes_Aes
End Class AesExample

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