.net core 使用MD5加密解密字符串

 /// <summary>
        /// 加密
        /// </summary>
        /// <param name="text">要加密的文本</param>
        /// <param name="skey">秘钥</param>
        /// <returns></returns>
        public static string encrypt(string text, string skey="test")
        {
            descryptoserviceprovider des = new descryptoserviceprovider();
            byte[] inputbytearray;
            inputbytearray = encoding.default.getbytes(text);
            des.key = asciiencoding.ascii.getbytes(md5hash(skey).substring(0,8));
            des.iv = asciiencoding.ascii.getbytes(md5hash(skey).substring(0, 8));
            system.io.memorystream ms = new system.io.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);
            }
            md4j= ret.tostring();
            return ret.tostring();
        }

/// <summary>
        /// 解密
        /// </summary>
        /// <param name="text"></param>
        /// <param name="skey"></param>
        /// <returns></returns>
        public static string decrypt(string text, string skey = "test")
        {
            descryptoserviceprovider des = new descryptoserviceprovider();
            int len;
            len = text.length / 2;
            byte[] inputbytearray = new byte[len];
            int x, i;
            for (x = 0; x < len; x++)
            {
                i = convert.toint32(text.substring(x * 2, 2), 16);
                inputbytearray[x] = (byte)i;
            }
            des.key = asciiencoding.ascii.getbytes(md5hash(skey).substring(0, 8));
            des.iv = asciiencoding.ascii.getbytes(md5hash(skey).substring(0, 8));
            system.io.memorystream ms = new system.io.memorystream();
            cryptostream cs = new cryptostream(ms, des.createdecryptor(), cryptostreammode.write);
            cs.write(inputbytearray, 0, inputbytearray.length);
            cs.flushfinalblock();
            return encoding.default.getstring(ms.toarray());
        }

 /// <summary>
        /// 32位md5加密
        /// </summary>
        /// <param name="input"></param>
        /// <returns></returns>
        private static string md5hash(string input)
        {
            md5cryptoserviceprovider md5hasher = new md5cryptoserviceprovider();
            byte[] data = md5hasher.computehash(encoding.default.getbytes(input));
            stringbuilder sbuilder = new stringbuilder();
            for (int i = 0; i < data.length; i++)
            {
                sbuilder.append(data[i].tostring("x2"));
            }
            return sbuilder.tostring();
        }

调用加密 解密看效果

      public static string md4j = "";
        static void main(string[] args)
        {
            //加密
          encrypt("123456");
          decrypt(md4j);
        }