加密与解密

using System; using System.Security.Cryptography; using System.IO; using System.Text; class EncryptionAndDissection { //加密： public static string Encrypting(string strSource) { //把字符串放到byte数组中 byte[] bytIn = System.Text.Encoding.Default.GetBytes(strSource); //建立加密对象的密钥和偏移量 byte[] iv = { 102, 16, 93, 156, 78, 4, 218, 32 };//定义偏移量 byte[] key = { 55, 103, 246, 79, 36, 99, 167, 3 };//定义密钥 //实例DES加密类 DESCryptoServiceProvider mobjCryptoService = new DESCryptoServiceProvider(); mobjCryptoService.Key = iv; mobjCryptoService.IV = key; ICryptoTransform encrypto = mobjCryptoService.CreateEncryptor(); //实例MemoryStream流加密密文件 System.IO.MemoryStream ms = new System.IO.MemoryStream(); CryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Write); cs.Write(bytIn, 0, bytIn.Length); cs.FlushFinalBlock(); return System.Convert.ToBase64String(ms.ToArray()); } //解密： public static string Decrypting(string Source) { try { //将解密字符串转换成字节数组 byte[] bytIn = System.Convert.FromBase64String(Source); //给出解密的密钥和偏移量，密钥和偏移量必须与加密时的密钥和偏移量相同 byte[] iv = { 102, 16, 93, 156, 78, 4, 218, 32 };//定义偏移量 byte[] key = { 55, 103, 246, 79, 36, 99, 167, 3 };//定义密钥 DESCryptoServiceProvider mobjCryptoService = new DESCryptoServiceProvider(); mobjCryptoService.Key = iv; mobjCryptoService.IV = key; //实例流进行解密 System.IO.MemoryStream ms = new System.IO.MemoryStream(bytIn, 0, bytIn.Length); ICryptoTransform encrypto = mobjCryptoService.CreateDecryptor(); CryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Read); StreamReader strd = new StreamReader(cs, Encoding.Default); return strd.ReadToEnd(); } catch (Exception ex) { throw new Exception("在文件解密的时候出现错误！错误提示： \n" + ex.Message); } } }