C# implements the encryption and decryption class instance based on Base64

using System;
using ; 
using ;
namespace 
{
 /// <summary>
 /// Summary description of Encrypt. /// </summary>
 public class DEncrypt
 {
  /// <summary>
  /// Construct method  /// </summary>
  public DEncrypt() 
  { 
  } 
  #region Use default key string Encryption/decryption string  /// <summary>
  /// Encrypt string with default key string  /// </summary>
  /// <param name="original">Plaintext</param>  /// <returns>ciphertext</returns>  public static string Encrypt(string original)
  {
   return Encrypt(original,"");
  }
  /// &lt;summary&gt;
  /// Decrypt string using default key string  /// &lt;/summary&gt;
  /// <param name="original">ciphertext</param>  /// <returns>Plain text</returns>  public static string Decrypt(string original)
  {
   return Decrypt(original,"",);
  }
  #endregion
  #region Use the given key string Encryption/decryption string  /// &lt;summary&gt;
  /// Encrypt string with the given key string  /// &lt;/summary&gt;
  /// <param name="original">original text</param>  /// <param name="key">key</param>  /// <param name="encoding">character encoding scheme</param>  /// <returns>ciphertext</returns>  public static string Encrypt(string original, string key) 
  { 
   byte[] buff = (original); 
   byte[] kb = (key);
   return Convert.ToBase64String(Encrypt(buff,kb));   
  }
  /// &lt;summary&gt;
  /// Decrypt string using the given key string  /// &lt;/summary&gt;
  /// <param name="original">ciphertext</param>  /// <param name="key">key</param>  /// <returns>Plain text</returns>  public static string Decrypt(string original, string key)
  {
   return Decrypt(original,key,);
  }
  /// &lt;summary&gt;
  /// Decrypt the string using the given key string, return the specified encoding method plaintext  /// &lt;/summary&gt;
  /// <param name="encrypted">ciphertext</param>  /// <param name="key">key</param>  /// <param name="encoding">character encoding scheme</param>  /// <returns>Plain text</returns>  public static string Decrypt(string encrypted, string key,Encoding encoding) 
  {    
   byte[] buff = Convert.FromBase64String(encrypted); 
   byte[] kb = (key);
   return (Decrypt(buff,kb));   
  } 
  #endregion
  #region Use default key string Encryption/decryption/byte[]  /// &lt;summary&gt;
  /// Decrypt byte[] using default key string  /// &lt;/summary&gt;
  /// <param name="encrypted">ciphertext</param>  /// <param name="key">key</param>  /// <returns>Plain text</returns>  public static byte[] Decrypt(byte[] encrypted) 
  { 
   byte[] key = (""); 
   return Decrypt(encrypted,key);   
  }
  /// &lt;summary&gt;
  /// Encrypt with default key string  /// &lt;/summary&gt;
  /// <param name="original">Raw data</param>  /// <param name="key">key</param>  /// <returns>ciphertext</returns>  public static byte[] Encrypt(byte[] original) 
  { 
   byte[] key = (""); 
   return Encrypt(original,key);   
  } 
  #endregion
  #region Use the given key to encrypt/decrypt/byte[]  /// &lt;summary&gt;
  /// Generate MD5 summary  /// &lt;/summary&gt;
  /// <param name="original">Data source</param>  /// <returns> Summary</returns>  public static byte[] MakeMD5(byte[] original)
  {
   MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();  
   byte[] keyhash = (original);    
   hashmd5 = null; 
   return keyhash;
  }
  /// &lt;summary&gt;
  /// Encrypt with the given key  /// &lt;/summary&gt;
  /// <param name="original">Plaintext</param>  /// <param name="key">key</param>  /// <returns>ciphertext</returns>  public static byte[] Encrypt(byte[] original, byte[] key) 
  { 
   TripleDESCryptoServiceProvider des = new TripleDESCryptoServiceProvider();    
    = MakeMD5(key);
    = ; 
   return ().TransformFinalBlock(original, 0, );   
  } 
  /// &lt;summary&gt;
  /// Decrypt data with the given key  /// &lt;/summary&gt;
  /// <param name="encrypted">ciphertext</param>  /// <param name="key">key</param>  /// <returns>Plain text</returns>  public static byte[] Decrypt(byte[] encrypted, byte[] key) 
  { 
   TripleDESCryptoServiceProvider des = new TripleDESCryptoServiceProvider(); 
    = MakeMD5(key);  
    = ; 
   return ().TransformFinalBlock(encrypted, 0, );
  } 
  #endregion
 }
}