微信小程序解密得到unoinid和手机号（开放数据的校验和解密获取手机号）

实际测试两种方法都可以：

第一种方法：

        public static string DecodeUserInfo(string encryptedData, string iv, string code)

        {

            var url = "https://api.weixin.qq.com/sns/jscode2session?appid=微信AppID&secret=开发秘钥&js_code=" + code + "&grant_type=authorization_code";

            var sessionkey = Utils.HttpGet(url);

            var wxinfo = Newtonsoft.Json.JsonConvert.DeserializeObject<WxInfoRequest>(sessionkey);

            var session_key = wxinfo.session_key;

            byte[] iv2 = Convert.FromBase64String(iv);

            if (string.IsNullOrEmpty(encryptedData)) return "";

            Byte[] toEncryptArray = Convert.FromBase64String(encryptedData);

            System.Security.Cryptography.RijndaelManaged rm = new System.Security.Cryptography.RijndaelManaged

            {

                Key = Convert.FromBase64String(session_key),

                IV = iv2,

                Mode = System.Security.Cryptography.CipherMode.CBC,

                Padding = System.Security.Cryptography.PaddingMode.PKCS7

            };

            System.Security.Cryptography.ICryptoTransform cTransform = rm.CreateDecryptor();

            Byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, , toEncryptArray.Length);

            return Encoding.UTF8.GetString(resultArray);

        }

第二中方法：

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace YouNameSpace

{

    using Newtonsoft.Json;

    using System;

    using System.Collections.Generic;

    using System.IO;

    using System.Linq;

    using System.Security.Cryptography;

    using System.Text;

    /// <summary>

    /// 签名及加密帮助类

    /// </summary>

    public static class EncryptHelper

    {

        #region 私有方法

        private static byte[] AES_Decrypt(String Input, byte[] Iv, byte[] Key)

        {

            RijndaelManaged aes = new RijndaelManaged();

#if NET45

#else

            //SymmetricAlgorithm aes = Aes.Create();

#endif

            aes.KeySize = ;//原始：256

            aes.BlockSize = ;

            aes.Mode = CipherMode.CBC;

            aes.Padding = PaddingMode.PKCS7;

            aes.Key = Key;

            aes.IV = Iv;

            var decrypt = aes.CreateDecryptor(aes.Key, aes.IV);

            byte[] xBuff = null;

            using (var ms = new MemoryStream())

            {

                using (var cs = new CryptoStream(ms, decrypt, CryptoStreamMode.Write))

                {

                    byte[] xXml = Convert.FromBase64String(Input);

                    byte[] msg = new byte[xXml.Length +  - xXml.Length % ];

                    Array.Copy(xXml, msg, xXml.Length);

                    cs.Write(xXml, , xXml.Length);

                }

                xBuff = decode2(ms.ToArray());

            }

            return xBuff;

        }

        private static byte[] decode2(byte[] decrypted)

        {

            int pad = (int)decrypted[decrypted.Length - ];

            if (pad <  || pad > )

            {

                pad = ;

            }

            byte[] res = new byte[decrypted.Length - pad];

            Array.Copy(decrypted, , res, , decrypted.Length - pad);

            return res;

        }

        #endregion

        /// <summary>

        /// 解密所有消息的基础方法

        /// </summary>

        /// <param name = "sessionKey" > 储存在 SessionBag 中的当前用户 会话 SessionKey</param>

        /// <param name = "encryptedData" > 接口返回数据中的 encryptedData 参数</param>

        /// <param name = "iv" > 接口返回数据中的 iv 参数，对称解密算法初始向量</param>

        //    / <returns></returns>

        public static string DecodeEncryptedData(string sessionKey, string encryptedData, string iv)

        {

            var aesCipher = Convert.FromBase64String(encryptedData);

            var aesKey = Convert.FromBase64String(sessionKey);

            var aesIV = Convert.FromBase64String(iv);

            var result = AES_Decrypt(encryptedData, aesIV, aesKey);

            var resultStr = Encoding.UTF8.GetString(result);

            return resultStr;

        }

    }

}

注意：1.session_key 是通过wx.login 然后得到code 然后去后台调取相应的接口获得的

2.如果你的小程序没有绑定微信开放平台，encryptedData 解密的数据中不包含unionid参数

3.微信开放平台和微信公众平台不是一回事需要单独注册的

4.解密encryptedData 之前最好先进行数据签名校验防止数据被篡改

（如果不进行校验解密的数据是被篡改的数据会导致得到的数据不准确上述例子中没做校验

校验主要用的是sha1加密在另一篇博文（https://www.cnblogs.com/huangshuqiang/p/6254023.html）中已经给出了sha1加密的写法）

参考：https://blog.****.net/willianyy/article/details/79670750

http://www.cnblogs.com/Sea1ee/p/9627021.html

微信小程序解密得到unoinid和手机号 （开放数据的校验和解密 获取手机号）

微信小程序解密得到unoinid和手机号（开放数据的校验和解密获取手机号）