using System;
using System.IO;
using System.Security.Cryptography; namespace RijndaelManaged_Example
{
class RijndaelExample
{
public static void Main()
{
try
{ string original = "Here is some data to encrypt!"; // Create a new instance of the Rijndael
// class. This generates a new key and initialization
// vector (IV).
using (Rijndael myRijndael = Rijndael.Create())
{
// Encrypt the string to an array of bytes.
byte[] encrypted = EncryptStringToBytes(original, myRijndael.Key, myRijndael.IV); // Decrypt the bytes to a string.
string roundtrip = DecryptStringFromBytes(encrypted, myRijndael.Key, myRijndael.IV); //Display the original data and the decrypted data.
Console.WriteLine("Original: {0}", original);
Console.WriteLine("Round Trip: {0}", roundtrip);
} }
catch (Exception e)
{
Console.WriteLine("Error: {0}", e.Message);
}
}
static byte[] EncryptStringToBytes(string plainText, byte[] Key, byte[] IV)
{
// Check arguments.
if (plainText == null || plainText.Length <= )
throw new ArgumentNullException("plainText");
if (Key == null || Key.Length <= )
throw new ArgumentNullException("Key");
if (IV == null || IV.Length <= )
throw new ArgumentNullException("Key");
byte[] encrypted;
// Create an Rijndael object
// with the specified key and IV.
using (Rijndael rijAlg = Rijndael.Create())
{
rijAlg.Key = Key;
rijAlg.IV = IV; // Create a decrytor to perform the stream transform.
ICryptoTransform encryptor = rijAlg.CreateEncryptor(rijAlg.Key, rijAlg.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(byte[] cipherText, byte[] Key, byte[] IV)
{
// Check arguments.
if (cipherText == null || cipherText.Length <= )
throw new ArgumentNullException("cipherText");
if (Key == null || Key.Length <= )
throw new ArgumentNullException("Key");
if (IV == null || IV.Length <= )
throw new ArgumentNullException("Key"); // Declare the string used to hold
// the decrypted text.
string plaintext = null; // Create an Rijndael object
// with the specified key and IV.
using (Rijndael rijAlg = Rijndael.Create())
{
rijAlg.Key = Key;
rijAlg.IV = IV; // Create a decrytor to perform the stream transform.
ICryptoTransform decryptor = rijAlg.CreateDecryptor(rijAlg.Key, rijAlg.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; }
}
}
原文地址：https://msdn.microsoft.com/zh-cn/library/system.security.cryptography.cryptostream.aspx