加密解密

using System;
using System.Security.Cryptography;
using System.Text;

namespace ManageSystem.Core {
    public static class CryptographyHelper {
        /// <summary> 
        /// MD5加密字符串 WEB
        /// </summary> 
        /// <param name="source">源字符串</param> 
        /// <returns>加密后的字符串</returns> 
        public string MD5(string source) {
            return FormsAuthentication.HashPasswordForStoringInConfigFile(source, "MD5"); ;
        }
        /// <summary>
        /// MD5 32位加密
        /// </summary>
        public static string MD5Encrypt32(string strCode) {
            MD5 md5 = new MD5CryptoServiceProvider();
            byte[] t = md5.ComputeHash(Encoding.UTF8.GetBytes(strCode));
            StringBuilder sb = new StringBuilder(32);
            for (int i = 0; i < t.Length; i++) {
                sb.Append(t[i].ToString("x").PadLeft(2, '0'));
            }
            return sb.ToString();
        }
        /// <summary>
        /// MD5 16位加密
        /// </summary>
        public static string MD5Encrypt16(string strCode) {
            MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
            string t2 = BitConverter.ToString(md5.ComputeHash(Encoding.UTF8.GetBytes(strCode)), 4, 8);
            t2 = t2.Replace("-", "");
            return t2;
        }

        // Methods
        public static string TripleDESDecrypt(string cipherString, string key, bool useHashing) {
            byte[] buffer;
            byte[] inputBuffer = Convert.FromBase64String(cipherString);
            //string key = "johnny depp";
            if (useHashing) {
                MD5CryptoServiceProvider provider = new MD5CryptoServiceProvider();
                buffer = provider.ComputeHash(Encoding.UTF8.GetBytes(key));
                provider.Clear();
            }
            else {
                buffer = Encoding.UTF8.GetBytes(key);
            }
            TripleDESCryptoServiceProvider tripleDesProvider = new TripleDESCryptoServiceProvider();
            tripleDesProvider.Key = buffer;
            tripleDesProvider.Mode = CipherMode.ECB;
            tripleDesProvider.Padding = PaddingMode.PKCS7;
            byte[] bytes = tripleDesProvider.CreateDecryptor().TransformFinalBlock(inputBuffer, 0, inputBuffer.Length);
            tripleDesProvider.Clear();
            return Encoding.UTF8.GetString(bytes);
        }

        public static string TripleDESEncrypt(string toEncrypt, string key, bool useHashing) {
            byte[] buffer;
            byte[] bytes = Encoding.UTF8.GetBytes(toEncrypt);
            //string key = "johnny depp";
            if (useHashing) {
                MD5CryptoServiceProvider provider = new MD5CryptoServiceProvider();
                buffer = provider.ComputeHash(Encoding.UTF8.GetBytes(key));
                provider.Clear();
            }
            else {
                buffer = Encoding.UTF8.GetBytes(key);
            }
            TripleDESCryptoServiceProvider tripleDesProvider = new TripleDESCryptoServiceProvider();
            tripleDesProvider.Key = buffer;
            tripleDesProvider.Mode = CipherMode.ECB;
            tripleDesProvider.Padding = PaddingMode.PKCS7;
            byte[] inArray = tripleDesProvider.CreateEncryptor().TransformFinalBlock(bytes, 0, bytes.Length);
            tripleDesProvider.Clear();
            return Convert.ToBase64String(inArray, 0, inArray.Length);
        }
    }
}