3DES对称加密算法C# 实现using System;using System.Web.Security;using System.Security;using System.Security.Cryptography;using System.Text;using System.IO;namespace CommonTools{/// <summary>/// 3DES的摘要说明。/// </summary>public class 3DES{ public 3DES() { // // TODO: 在此处添加构造函数逻辑 // } #region 3DES加密/解密 //密钥 //sKey输入密码的时候,必须使用英文字符,区分大小写,且字符数量是8个,不能多也不能少,否则出错。 private const string sKey = "AqjWCgRP"; //矢量,矢量可以为空 private const string sIV = "YnExToNe"; //构造一个对称算法 #region public string EncryptString(string ToEntryptString) /// <summary> /// 使用DES加密字符串 /// </summary> /// <param name="ToEntryptString">需要加密的字符串</param> /// <returns>加密结果字符串</returns> public static string EncryptStringBy3DES(string ToEntryptString) { DESCryptoServiceProvider des = new DESCryptoServiceProvider(); //把字符串放到byte数组中 byte[] inputByteArray = Encoding.Default.GetBytes(ToEntryptString); //建立加密对象的密钥和偏移量 des.Key = ASCIIEncoding.ASCII.GetBytes(sKey); des.IV = ASCIIEncoding.ASCII.GetBytes(sIV); MemoryStream ms = new MemoryStream(); CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write); cs.Write(inputByteArray, 0, inputByteArray.Length); cs.FlushFinalBlock(); StringBuilder ret = new StringBuilder(); foreach (byte b in ms.ToArray()) { ret.AppendFormat("{0:X2}", b); } ret.ToString(); return ret.ToString(); } #endregion #region public string DecryptString(string Value) /// <summary> /// 解密DES加密字符串 /// </summary> /// <param name="ToDecryptString">解密字符串</param> /// <returns>解密结果字符串</returns> public static string DecryptStringBy3DES(string ToDecryptString) { DESCryptoServiceProvider des = new DESCryptoServiceProvider(); //Put the input string into the byte array byte[] inputByteArray = new byte[ToDecryptString.Length / 2]; for (int x = 0; x < ToDecryptString.Length / 2; x++) { int i = (Convert.ToInt32(ToDecryptString.Substring(x * 2, 2), 16)); inputByteArray[x] = (byte)i; } //建立加密对象的密钥和偏移量,此值重要,不能修改 des.Key = ASCIIEncoding.ASCII.GetBytes(sKey); des.IV = ASCIIEncoding.ASCII.GetBytes(sIV); MemoryStream ms = new MemoryStream(); CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write); //Flush the data through the crypto stream into the memory stream cs.Write(inputByteArray, 0, inputByteArray.Length); cs.FlushFinalBlock(); //Get the decrypted data back from the memory stream //建立StringBuild对象,CreateDecrypt使用的是流对象,必须把解密后的文本变成流对象 StringBuilder ret = new StringBuilder(); return System.Text.Encoding.Default.GetString(ms.ToArray()); } #endregion #endregion }}