C# Aes加密算法

 1         /// <summary>
 2         /// AES加密 对应java中的 aes/cbc/pkcs5padding 模式的算法
 3         /// </summary>
 4         /// <param name="s">待加密的字符串</param>
 5         /// <param name="sKey">密钥</param>
 6         /// <returns></returns>
 7         public static string AesEncrypt(string s, string sKey)
 8         {
 9             AesCryptoServiceProvider provider = new AesCryptoServiceProvider();
10             if (sKey == null)
11             {
12                 throw new Exception("Key为空null");
13             }
14             // 判断Key是否为16位
15             if (sKey.Length != 16)
16             {
17                 throw new Exception("Key长度不是16位");
18             }
19             byte[] bytes = Encoding.UTF8.GetBytes(s);
20             provider.Key = Encoding.UTF8.GetBytes(sKey);
21             provider.IV = Encoding.UTF8.GetBytes("0102030405060708");
22             MemoryStream stream = new MemoryStream();
23             CryptoStream stream2 = new CryptoStream(stream, provider.CreateEncryptor(), CryptoStreamMode.Write);
24             stream2.Write(bytes, 0, bytes.Length);
25             stream2.FlushFinalBlock();
26             StringBuilder builder = new StringBuilder();
27             foreach (byte num in stream.ToArray())
28             {
29                 builder.AppendFormat("{0:X2}", num);
30             }
31             builder.ToString();
32             stream2.Close();
33             stream.Close();
34             return builder.ToString();
35         }
36
37         /// <summary>
38         /// AES解密  对应java中的 aes/cbc/pkcs5padding 模式的算法
39         /// </summary>
40         /// <param name="s">待解密的字符串</param>
41         /// <param name="sKey">密钥</param>
42         /// <returns></returns>
43         public static string AesDecrypt(string s, string sKey)
44         {
45             AesCryptoServiceProvider provider = new AesCryptoServiceProvider();
46             byte[] buffer = new byte[s.Length / 2];
47             for (int i = 0; i < (s.Length / 2); i++)
48             {
49                 int num2 = Convert.ToInt32(s.Substring(i * 2, 2), 0x10);
50                 buffer[i] = (byte)num2;
51             }
52             provider.Key = Encoding.UTF8.GetBytes(sKey);
53             provider.IV = Encoding.UTF8.GetBytes("0102030405060708");
54             MemoryStream stream = new MemoryStream();
55             CryptoStream stream2 = new CryptoStream(stream, provider.CreateDecryptor(), CryptoStreamMode.Write);
56             stream2.Write(buffer, 0, buffer.Length);
57             stream2.FlushFinalBlock();
58             StringBuilder builder = new StringBuilder();
59             stream2.Close();
60             stream.Close();
61             return Encoding.Default.GetString(stream.ToArray());
62         }