c# 实现MD5，SHA1，SHA256，SHA512等常用加密算法

using System; using System.IO; using System.Data; using System.Text; using System.Diagnostics; using System.Security; using System.Security.Cryptography; /**//* * .Net框架由于拥有CLR提供的丰富库支持，只需很少的代码即可实现先前使用C等旧式语言很难实现的加密算法。本类实现一些常用机密算法，供参考。其中MD5算法返回Int的ToString字串。返回数字字母型结果的算法参见之前Blog文章 */ namespace 档案数字化加工 { /**//// <summary> /// 类名：HashEncrypt /// 作用：对传入的字符串进行Hash运算，返回通过Hash算法加密过的字串。 /// 属性：［无］ /// 构造函数额参数： /// IsReturnNum:是否返回为加密后字符的Byte代码 /// IsCaseSensitive：是否区分大小写。 /// 方法：此类提供MD5，SHA1，SHA256，SHA512等四种算法，加密字串的长度依次增大。 /// </summary> public class HashEncrypt { //private string strIN; private bool isReturnNum; private bool isCaseSensitive; /**//// <summary> /// 类初始化，此类提供MD5，SHA1，SHA256，SHA512等四种算法，加密字串的长度依次增大。 /// </summary> /// <param name="IsCaseSensitive">是否区分大小写</param> /// <param name="IsReturnNum">是否返回为加密后字符的Byte代码</param> public HashEncrypt(bool IsCaseSensitive, bool IsReturnNum) { this.isReturnNum = IsReturnNum; this.isCaseSensitive = IsCaseSensitive; } private string getstrIN(string strIN) { //string strIN = strIN; if (strIN.Length == 0) { strIN = "NULL"; } if (isCaseSensitive == false) { strIN = strIN.ToUpper(); } return strIN; } public string MD5Encrypt(string strIN) { //string strIN = getstrIN(strIN); byte[] tmpByte; MD5 md5 = new MD5CryptoServiceProvider(); tmpByte = md5.ComputeHash(GetKeyByteArray(getstrIN(strIN))); md5.Clear(); return GetStringValue(tmpByte); } public string SHA1Encrypt(string strIN) { //string strIN = getstrIN(strIN); byte[] tmpByte; SHA1 sha1 = new SHA1CryptoServiceProvider(); tmpByte = sha1.ComputeHash(GetKeyByteArray(strIN)); sha1.Clear(); return GetStringValue(tmpByte); } public string SHA256Encrypt(string strIN) { //string strIN = getstrIN(strIN); byte[] tmpByte; SHA256 sha256 = new SHA256Managed(); tmpByte = sha256.ComputeHash(GetKeyByteArray(strIN)); sha256.Clear(); return GetStringValue(tmpByte); } public string SHA512Encrypt(string strIN) { //string strIN = getstrIN(strIN); byte[] tmpByte; SHA512 sha512 = new SHA512Managed(); tmpByte = sha512.ComputeHash(GetKeyByteArray(strIN)); sha512.Clear(); return GetStringValue(tmpByte); } /**//// <summary> /// 使用DES加密（Added by niehl 2005-4-6） /// </summary> /// <param name="originalValue">待加密的字符串</param> /// <param name="key">密钥(最大长度8)</param> /// <param name="IV">初始化向量(最大长度8)</param> /// <returns>加密后的字符串</returns> public string DESEncrypt(string originalValue, string key, string IV) { //将key和IV处理成8个字符 key += "12345678"; IV += "12345678"; key = key.Substring(0, 8); IV = IV.Substring(0, 8); SymmetricAlgorithm sa; ICryptoTransform ct; MemoryStream ms; CryptoStream cs; byte[] byt; sa = new DESCryptoServiceProvider(); sa.Key = Encoding.UTF8.GetBytes(key); sa.IV = Encoding.UTF8.GetBytes(IV); ct = sa.CreateEncryptor(); byt = Encoding.UTF8.GetBytes(originalValue); ms = new MemoryStream(); cs = new CryptoStream(ms, ct, CryptoStreamMode.Write); cs.Write(byt, 0, byt.Length); cs.FlushFinalBlock(); cs.Close(); return Convert.ToBase64String(ms.ToArray()); } public string DESEncrypt(string originalValue, string key) { return DESEncrypt(originalValue, key, key); } /**//// <summary> /// 使用DES解密（Added by niehl 2005-4-6） /// </summary> /// <param name="encryptedValue">待解密的字符串</param> /// <param name="key">密钥(最大长度8)</param> /// <param name="IV">m初始化向量(最大长度8)</param> /// <returns>解密后的字符串</returns> public string DESDecrypt(string encryptedValue, string key, string IV) { //将key和IV处理成8个字符 key += "12345678"; IV += "12345678"; key = key.Substring(0, 8); IV = IV.Substring(0, 8); SymmetricAlgorithm sa; ICryptoTransform ct; MemoryStream ms; CryptoStream cs; byte[] byt; sa = new DESCryptoServiceProvider(); sa.Key = Encoding.UTF8.GetBytes(key); sa.IV = Encoding.UTF8.GetBytes(IV); ct = sa.CreateDecryptor(); byt = Convert.FromBase64String(encryptedValue); ms = new MemoryStream(); cs = new CryptoStream(ms, ct, CryptoStreamMode.Write); cs.Write(byt, 0, byt.Length); cs.FlushFinalBlock(); cs.Close(); return Encoding.UTF8.GetString(ms.ToArray()); } public string DESDecrypt(string encryptedValue, string key) { return DESDecrypt(encryptedValue, key, key); } private string GetStringValue(byte[] Byte) { string tmpString = ""; if (this.isReturnNum == false) { ASCIIEncoding Asc = new ASCIIEncoding(); tmpString = Asc.GetString(Byte); } else { int iCounter; for (iCounter = 0; iCounter < Byte.Length; iCounter++) { tmpString = tmpString + Byte[iCounter].ToString(); } } return tmpString; } private byte[] GetKeyByteArray(string strKey) { ASCIIEncoding Asc = new ASCIIEncoding(); int tmpStrLen = strKey.Length; byte[] tmpByte = new byte[tmpStrLen – 1]; tmpByte = Asc.GetBytes(strKey); return tmpByte; } } }