Aes Constructor
Definition
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Initializes a new instance of the Aes class.
protected:
Aes();
protected Aes ();
Protected Sub New ()
Examples
The following example demonstrates how to encrypt and decrypt sample data using the Aes class.
using System;
using System.IO;
using System.Security.Cryptography;
namespace Aes_Example
{
class AesExample
{
public static void Main()
{
string original = "Here is some data to encrypt!";
// Create a new instance of the Aes
// class. This generates a new key and initialization
// vector (IV).
using (Aes myAes = Aes.Create())
{
// Encrypt the string to an array of bytes.
byte[] encrypted = EncryptStringToBytes_Aes(original, myAes.Key, myAes.IV);
// Decrypt the bytes to a string.
string roundtrip = 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);
}
}
static byte[] EncryptStringToBytes_Aes(string plainText, byte[] Key, byte[] IV)
{
// Check arguments.
if (plainText == null || plainText.Length <= 0)
throw new ArgumentNullException("plainText");
if (Key == null || Key.Length <= 0)
throw new ArgumentNullException("Key");
if (IV == null || IV.Length <= 0)
throw new ArgumentNullException("IV");
byte[] encrypted;
// Create an Aes object
// with the specified key and IV.
using (Aes aesAlg = Aes.Create())
{
aesAlg.Key = Key;
aesAlg.IV = IV;
// Create an encryptor to perform the stream transform.
ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);
// Create the streams used for encryption.
using (MemoryStream msEncrypt = new MemoryStream())
{
using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
{
using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
{
//Write all data to the stream.
swEncrypt.Write(plainText);
}
}
encrypted = msEncrypt.ToArray();
}
}
// Return the encrypted bytes from the memory stream.
return encrypted;
}
static string DecryptStringFromBytes_Aes(byte[] cipherText, byte[] Key, byte[] IV)
{
// Check arguments.
if (cipherText == null || cipherText.Length <= 0)
throw new ArgumentNullException("cipherText");
if (Key == null || Key.Length <= 0)
throw new ArgumentNullException("Key");
if (IV == null || IV.Length <= 0)
throw new ArgumentNullException("IV");
// Declare the string used to hold
// the decrypted text.
string plaintext = null;
// Create an Aes object
// with the specified key and IV.
using (Aes aesAlg = Aes.Create())
{
aesAlg.Key = Key;
aesAlg.IV = IV;
// Create a decryptor to perform the stream transform.
ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);
// Create the streams used for decryption.
using (MemoryStream msDecrypt = new MemoryStream(cipherText))
{
using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
{
using (StreamReader srDecrypt = new StreamReader(csDecrypt))
{
// Read the decrypted bytes from the decrypting stream
// and place them in a string.
plaintext = srDecrypt.ReadToEnd();
}
}
}
}
return plaintext;
}
}
}
Imports System.IO
Imports System.Security.Cryptography
Class AesExample
Public Shared Sub Main()
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)
End Using
End Sub
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("IV")
End If
Dim encrypted() As Byte
' Create an Aes object
' with the specified key and IV.
Using aesAlg As Aes = Aes.Create()
aesAlg.Key = Key
aesAlg.IV = IV
' Create an encryptor 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("IV")
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 decryptor 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
open System
open System.IO
open System.Security.Cryptography
let encryptStringToBytes_Aes (plainText: string, key : byte[], iv : byte[]) : byte[] =
// Check arguments.
if (isNull plainText || plainText.Length <= 0) then nullArg "plainText"
if (isNull key || key.Length <= 0) then nullArg "key"
if (isNull iv || iv.Length <= 0) then nullArg "iv"
// Create an Aes object
// with the specified key and IV.
use aesAlg = Aes.Create()
aesAlg.Key <- key
aesAlg.IV <- iv
// Create an encryptor to perform the stream transform.
let encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV)
// Create the streams used for encryption.
use msEncrypt = new MemoryStream()
use csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write)
use swEncrypt = new StreamWriter(csEncrypt)
//Write all data to the stream.
swEncrypt.Write(plainText)
swEncrypt.Flush()
// Return the encrypted bytes from the memory stream.
msEncrypt.ToArray()
let decryptStringFromBytes_Aes (cipherText : byte[], key : byte[], iv : byte[]) : string =
// Check arguments.
if (isNull cipherText || cipherText.Length <= 0) then nullArg "cipherText"
if (isNull key || key.Length <= 0) then nullArg "key"
if (isNull iv || iv.Length <= 0) then nullArg "iv"
// Create an Aes object
// with the specified key and IV.
use aesAlg = Aes.Create()
aesAlg.Key <- key
aesAlg.IV <- iv
// Create a decryptor to perform the stream transform.
let decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV)
// Create the streams used for decryption.
use msDecrypt = new MemoryStream(cipherText)
use csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read)
use srDecrypt = new StreamReader(csDecrypt)
// Read the decrypted bytes from the decrypting stream
// and return the resulting string.
srDecrypt.ReadToEnd()
[<EntryPoint>]
let main argv =
let original = "Here is some data to encrypt!"
// Create a new instance of the Aes
// class. This generates a new key and initialization
// vector (IV).
use myAes = Aes.Create()
// Encrypt the string to an array of bytes.
let encrypted = encryptStringToBytes_Aes(original, myAes.Key, myAes.IV)
// Decrypt the bytes to a string.
let roundtrip = 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)
0
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