Md5加密解密方法

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;

namespace Siia.Veima.Host.Utils
{
    public class CommonFunction
    {
        /// <summary>
        /// 32位MD5加密
        /// </summary>
        /// <param name="password"></param>
        /// <returns></returns>
        public static string MD5Encrypt32(string password)
        {
            //string cl = password;
            //string pwd = "";
            //MD5 md5 = MD5.Create(); //實例化一個md5對像
            //                        // 加密后是一個字節類型的數組，這里要注意編碼UTF8/Unicode等的選擇　
            //byte[] s = md5.ComputeHash(Encoding.UTF8.GetBytes(cl));
            //// 通過使用循環，將字節類型的數組轉換為字符串，此字符串是常規字符格式化所得
            //for (int i = 0; i < s.Length; i++)
            //{
            //    // 將得到的字符串使用十六進制類型格式。格式后的字符是小寫的字母，如果使用大寫（X）則格式后的字符是大寫字符 
            //    pwd = pwd + s[i].ToString("X");
            //}
            //return pwd;
            MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
            string t2 = BitConverter.ToString(md5.ComputeHash(UTF8Encoding.Default.GetBytes(password)));
            t2 = t2.Replace("-", "");
            return t2;
        }
        /// <summary>
        /// 加密
        /// </summary>
        /// <param name="characters">要加密的明文</param>
        /// <returns>加密后的密文</returns>
        public static string EncryptStr(string characters)
        {
            string key = "330ead0b-4951-46a7-8db8-0e2569472fd1";
            //位移加密
            byte[] bStr = (new UnicodeEncoding()).GetBytes(characters);

            for (int i = 0; i < bStr.Length; i++)
            {
                byte b = (byte)(bStr[i] + 255);
                bStr[i] = b;
            }
            byte[] bKey = (new UnicodeEncoding()).GetBytes(key);//加密鎖
            //異或加密
            for (int i = 0; i < bStr.Length; i += 2)
            {
                for (int j = 0; j < bKey.Length; j += 3)
                {
                    bStr[i] = Convert.ToByte(bStr[i] ^ bKey[j]);
                }
            }
            return (new UnicodeEncoding()).GetString(bStr).TrimEnd('\0');
        }
        /// <summary>
        /// 解密
        /// </summary>
        /// <param name="ciphertext">要解密的密文</param>
        /// <returns>解密后的明文</returns>
        public static string DecryptStr(string ciphertext)
        {
            string key = "330ead0b-4951-46a7-8db8-0e2569472fd1";
            byte[] bStr = (new UnicodeEncoding()).GetBytes(ciphertext);
            byte[] bKey = (new UnicodeEncoding()).GetBytes(key);//加密鎖
            //異或解密
            for (int i = 0; i < bStr.Length; i += 2)
            {
                for (int j = 0; j < bKey.Length; j += 3)
                {
                    bStr[i] = Convert.ToByte(bStr[i] ^ bKey[j]);
                }
            }
            //位移解密
            for (int i = 0; i < bStr.Length; i++)
            {
                byte b = (byte)(bStr[i] - 255);
                bStr[i] = b;
            }
            return (new UnicodeEncoding()).GetString(bStr).TrimEnd('\0');
        }


        //加密
        public static string Encryption(string express)
        {
            CspParameters param = new CspParameters();
            param.KeyContainerName = "siia";//密匙容器的名稱，保持加密解密一致才能解密成功
            using (RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(param))
            {
                byte[] plaindata = Encoding.Default.GetBytes(express);//將要加密的字符串轉換為字節數組
                byte[] encryptdata = rsa.Encrypt(plaindata, false);//將加密后的字節數據轉換為新的加密字節數組
                return Convert.ToBase64String(encryptdata);//將加密后的字節數組轉換為字符串
            }
        }

        //解密
        public static string Decrypt(string ciphertext)
        {
            CspParameters param = new CspParameters();
            param.KeyContainerName = "330ead0b-4951-46a7-8db8-0e2569472fd1";
            using (RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(param))
            {
                byte[] encryptdata = Convert.FromBase64String(ciphertext);
                byte[] decryptdata = rsa.Decrypt(encryptdata, false);
                return Encoding.Default.GetString(decryptdata);
            }
        }
    }
}