C#.NET 加密解密：AES/DES/Base64/RSA/MD5/SHA256

using System;

using System.Globalization;

using System.IO;

using System.Security.Cryptography;

using System.Text;



namespace Pub.Class

{

    public static class EncryptExtensions

    {

        private static readonly byte[] AESKeys = {0x41, 0x72, 0x65, 0x79, 0x6F, 0x75, 0x6D, 0x79, 0x53, 0x6E, 0x6F, 0x77, 0x6D, 0x61, 0x6E, 0x3F};

        private static readonly byte[] DESKeys = {0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF};



        public static string AESEncode(this string encryptString, string encryptKey)

        {

            encryptKey = encryptKey.SubString(32, "");

            encryptKey = encryptKey.PadRight(32, ' ');



            var rijndaelProvider = new RijndaelManaged();

            rijndaelProvider.Key = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 32));

            rijndaelProvider.IV = AESKeys;

            ICryptoTransform rijndaelEncrypt = rijndaelProvider.CreateEncryptor();



            byte[] inputData = Encoding.UTF8.GetBytes(encryptString);

            byte[] encryptedData = rijndaelEncrypt.TransformFinalBlock(inputData, 0, inputData.Length);



            return Convert.ToBase64String(encryptedData);

        }



        public static string AESDecode(this string decryptString, string decryptKey)

        {

            try

            {

                decryptKey = decryptKey.SubString(32, "");

                decryptKey = decryptKey.PadRight(32, ' ');



                var rijndaelProvider = new RijndaelManaged();

                rijndaelProvider.Key = Encoding.UTF8.GetBytes(decryptKey);

                rijndaelProvider.IV = AESKeys;

                ICryptoTransform rijndaelDecrypt = rijndaelProvider.CreateDecryptor();



                byte[] inputData = Convert.FromBase64String(decryptString);

                byte[] decryptedData = rijndaelDecrypt.TransformFinalBlock(inputData, 0, inputData.Length);



                return Encoding.UTF8.GetString(decryptedData);

            }

            catch

            {

                return string.Empty;

            }

        }



        public static string DESEncode(this string encryptString, string encryptKey)

        {

            encryptKey = encryptKey.SubString(8, "");

            encryptKey = encryptKey.PadRight(8, ' ');

            byte[] rgbKey = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 8));

            byte[] rgbIV = DESKeys;

            byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);

            var dCSP = new DESCryptoServiceProvider();

            var mStream = new MemoryStream();

            var cStream = new CryptoStream(mStream, dCSP.CreateEncryptor(rgbKey, rgbIV), CryptoStreamMode.Write);

            cStream.Write(inputByteArray, 0, inputByteArray.Length);

            cStream.FlushFinalBlock();

            return Convert.ToBase64String(mStream.ToArray());

        }



        public static string DESDecode(this string decryptString, string decryptKey)

        {

            try

            {

                decryptKey = decryptKey.SubString(8, "");

                decryptKey = decryptKey.PadRight(8, ' ');

                byte[] rgbKey = Encoding.UTF8.GetBytes(decryptKey);

                byte[] rgbIV = DESKeys;

                byte[] inputByteArray = Convert.FromBase64String(decryptString);

                var DCSP = new DESCryptoServiceProvider();



                var mStream = new MemoryStream();

                var cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write);

                cStream.Write(inputByteArray, 0, inputByteArray.Length);

                cStream.FlushFinalBlock();

                return Encoding.UTF8.GetString(mStream.ToArray());

            }

            catch

            {

                return string.Empty;

            }

        }



        public static string Base64Encode(this string encryptString)

        {

            byte[] encbuff = Encoding.UTF8.GetBytes(encryptString);

            return Convert.ToBase64String(encbuff);

        }



        public static string Base64Decode(this string decryptString)

        {

            byte[] decbuff = Convert.FromBase64String(decryptString);

            return Encoding.UTF8.GetString(decbuff);

        }



        public static string RSADecrypt(this string s, string key)

        {

            string result = null;



            if (string.IsNullOrEmpty(s)) throw new ArgumentException("An empty string value cannot be encrypted.");



            if (string.IsNullOrEmpty(key)) throw new ArgumentException("Cannot decrypt using an empty key. Please supply a decryption key.");



            var cspp = new CspParameters();

            cspp.KeyContainerName = key;



            var rsa = new RSACryptoServiceProvider(cspp);

            rsa.PersistKeyInCsp = true;



            string[] decryptArray = s.Split(new[] {"-"}, StringSplitOptions.None);

            byte[] decryptByteArray = Array.ConvertAll(decryptArray, (a => Convert.ToByte(byte.Parse(a, NumberStyles.HexNumber))));



            byte[] bytes = rsa.Decrypt(decryptByteArray, true);



            result = Encoding.UTF8.GetString(bytes);



            return result;

        }



        public static string RSAEncrypt(this string s, string key)

        {

            if (string.IsNullOrEmpty(s)) throw new ArgumentException("An empty string value cannot be encrypted.");



            if (string.IsNullOrEmpty(key)) throw new ArgumentException("Cannot encrypt using an empty key. Please supply an encryption key.");



            var cspp = new CspParameters();

            cspp.KeyContainerName = key;



            var rsa = new RSACryptoServiceProvider(cspp);

            rsa.PersistKeyInCsp = true;



            byte[] bytes = rsa.Encrypt(Encoding.UTF8.GetBytes(s), true);



            return BitConverter.ToString(bytes);

        }



        public static string MD5(this string str)

        {

            string cl1 = str;

            string pwd = "";

            MD5 md5 = System.Security.Cryptography.MD5.Create(); // 加密后是一个字节类型的数组 

            byte[] s = md5.ComputeHash(Encoding.Unicode.GetBytes(cl1));

            for (int i = 0; i < s.Length; i++)

            {

// 通过使用循环，将字节类型的数组转换为字符串，此字符串是常规字符格式化所得 

                pwd = pwd + s[i].ToString("x"); // 将得到的字符串使用十六进制类型格式。格式后的字符是小写的字母，如果使用大写（X）则格式后的字符是大写字符 

            }

            return pwd;

        }



        public static string MD5CSP(this string encypStr)

        {

            string retStr;

            var m5 = new MD5CryptoServiceProvider();



            //创建md5对象

            byte[] inputBye;

            byte[] outputBye;



            //使用GB2312编码方式把字符串转化为字节数组．

            inputBye = Encoding.GetEncoding("GB2312").GetBytes(encypStr);



            outputBye = m5.ComputeHash(inputBye);



            retStr = BitConverter.ToString(outputBye);

            retStr = retStr.Replace("-", "").ToLower();

            return retStr;

        }



        public static string SHA256(this string str)

        {

            byte[] SHA256Data = Encoding.UTF8.GetBytes(str);

            var Sha256 = new SHA256Managed();

            byte[] Result = Sha256.ComputeHash(SHA256Data);

            return Convert.ToBase64String(Result); //返回长度为44字节的字符串

        }

    }

}