C#微信小程序服务端获取用户解密信息

using AIOWeb.Models;  
using Newtonsoft.Json;  
using Newtonsoft.Json.Linq;  
using System;  
using System.Collections.Generic;  
using System.Data;  
using System.Data.SqlClient;  
using System.Linq;  
using System.Web;  
namespace AIOWeb  
{  
    /// <summary>  
    /// wxapi 的摘要说明  
    /// </summary>  
    public class wxapi : IHttpHandler  
    {  
        public void ProcessRequest(HttpContext context)  
        {  
            context.Response.ContentType = "text/plain";  
            string code = "";  
            string iv = "";  
            string encryptedData = "";  
            try  
            {  
                code = HttpContext.Current.Request.QueryString["code"].ToString();  
                iv = HttpContext.Current.Request.QueryString["iv"].ToString();  
                encryptedData = HttpContext.Current.Request.QueryString["encryptedData"].ToString();  
            }  
            catch (Exception ex)  
            {  
                context.Response.Write(ex.ToString());  
            }  
            string Appid = "wxdb2641f85b04f1b3";  
            string Secret = "8591d8cd7197b9197e17b3275329a1e7";  
            string grant_type = "authorization_code";  
            //向微信服务端 使用登录凭证 code 获取 session_key 和 openid   
            string url = "" + Appid + "&secret=" + Secret + "&js_code=" + code + "&grant_type=" + grant_type;  
            string type = "utf-8";  
            AIOWeb.Models.GetUsersHelper GetUsersHelper = new AIOWeb.Models.GetUsersHelper();  
            string j = GetUsersHelper.GetUrltoHtml(url, type);//获取微信服务器返回字符串  
            //将字符串转换为json格式  
            JObject jo = (JObject)JsonConvert.DeserializeObject(j);  
            result res = new result();  
            try  
            {  
                //微信服务器验证成功  
                res.openid = jo["openid"].ToString();  
                res.session_key = jo["session_key"].ToString();  
            }  
            catch (Exception)  
            {  
                //微信服务器验证失败  
                res.errcode = jo["errcode"].ToString();  
                res.errmsg = jo["errmsg"].ToString();  
            }  
            if (!string.IsNullOrEmpty(res.openid))  
            {  
                //用户数据解密  
                GetUsersHelper.AesIV = iv;  
                GetUsersHelper.AesKey = res.session_key;  
                string result = GetUsersHelper.AESDecrypt(encryptedData);  
                //存储用户数据  
                JObject _usrInfo = (JObject)JsonConvert.DeserializeObject(result);  
                userInfo userInfo = new userInfo();  
                userInfo.openId = _usrInfo["openId"].ToString();  
                try //部分验证返回值中没有unionId  
                {  
                    userInfo.unionId = _usrInfo["unionId"].ToString();  
                }  
                catch (Exception)  
                {  
                    userInfo.unionId = "unionId";  
                }  
                userInfo.nickName = _usrInfo["nickName"].ToString();  
                userInfo.gender = _usrInfo["gender"].ToString();  
                userInfo.city = _usrInfo["city"].ToString();  
                userInfo.province = _usrInfo["province"].ToString();  
                userInfo.country = _usrInfo["country"].ToString();  
                userInfo.avatarUrl = _usrInfo["avatarUrl"].ToString();  
                object watermark = _usrInfo["watermark"].ToString();  
                object appid = _usrInfo["watermark"]["appid"].ToString();  
                object timestamp = _usrInfo["watermark"]["timestamp"].ToString();  
                #region  
                //创建连接池对象（与数据库服务器进行连接）  
                SqlConnection conn = new SqlConnection("server=127.0.0.1;database=Test;uid=sa;pwd=1");  
                //打开连接池  
                conn.Open();  
                //创建命令对象  
                string Qrystr = "SELECT * FROM WeChatUsers WHERE openId='" + userInfo.openId + "'";  
                SqlCommand cmdQry = new SqlCommand(Qrystr, conn);  
                object  obj = cmdQry.ExecuteScalar();  
                if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))  
                {  
                    string str = "INSERT INTO WeChatUsers ([UnionId] ,[OpenId],[NickName],[Gender],[City],[Province],[Country],[AvatarUrl],[Appid],[Timestamp],[Memo],[counts])VALUES('" + userInfo.unionId + "','" + userInfo.openId + "','" + userInfo.nickName + "','" + userInfo.gender + "','" + userInfo.city + "','" + userInfo.province + "','" + userInfo.country + "','" + userInfo.avatarUrl + "','" + appid.ToString() + "','" + timestamp.ToString() + "','来自微信小程序','1')";  
                    SqlCommand cmdUp = new SqlCommand(str, conn);  
                    // 执行操作  
                    try  
                    {  
                        int row = cmdUp.ExecuteNonQuery();  
                    }  
                    catch (Exception ex)  
                    {  
                        context.Response.Write(ex.ToString());  
                    }  
                }  
                else  
                {  
                    //多次访问，记录访问次数counts   更新unionId是预防最初没有，后期关联后却仍未记录  
                    string str = "UPDATE dbo.WeChatUsers SET counts = counts+1，UnionId = '" + userInfo.unionId + "' WHERE OpenId='" + userInfo.openId + "'";  
                    SqlCommand cmdUp = new SqlCommand(str, conn);  
                    int row = cmdUp.ExecuteNonQuery();  
                }  
                //关闭连接池  
                conn.Close();  
                #endregion  
                //返回解密后的用户数据  
                context.Response.Write(result);  
            }  
            else  
            {  
                context.Response.Write(j);  
            }  
        }  
        public bool IsReusable  
        {  
            get  
            {  
                return false;  
            }  
        }  
    }  
}  

GetUsersHelper 帮助类

using System;  
using System.Collections.Generic;  
using System.IO;  
using System.Linq;  
using System.Security.Cryptography;  
using System.Text;  
using System.Threading.Tasks;  
namespace AIOWeb.Models  
{  
    public class GetUsersHelper  
    {  
        /// <summary>  
        /// 获取链接返回数据  
        /// </summary>  
        /// <param name="Url">链接</param>  
        /// <param name="type">请求类型</param>  
        /// <returns></returns>  
        public  string GetUrltoHtml(string Url, string type)  
        {  
            try  
            {  
                System.Net.WebRequest wReq = System.Net.WebRequest.Create(Url);  
                // Get the response instance.  
                System.Net.WebResponse wResp = wReq.GetResponse();  
                System.IO.Stream respStream = wResp.GetResponseStream();  
                // Dim reader As StreamReader = New StreamReader(respStream)  
                using (System.IO.StreamReader reader = new System.IO.StreamReader(respStream, Encoding.GetEncoding(type)))  
                {  
                    return reader.ReadToEnd();  
                }  
            }  
            catch (System.Exception ex)  
            {  
                return ex.Message;  
            }  
        }  
        #region 微信小程序用户数据解密  
        public static string AesKey;  
        public static string AesIV;  
        /// <summary>  
        /// AES解密  
        /// </summary>  
        /// <param name="inputdata">输入的数据encryptedData</param>  
        /// <param name="AesKey">key</param>  
        /// <param name="AesIV">向量128</param>  
        /// <returns name="result">解密后的字符串</returns>  
        public string AESDecrypt(string inputdata)  
        {  
            try  
            {  
                AesIV = AesIV.Replace(" ", "+");  
                AesKey = AesKey.Replace(" ", "+");  
                inputdata = inputdata.Replace(" ", "+");  
                byte[] encryptedData = Convert.FromBase64String(inputdata);  
                RijndaelManaged rijndaelCipher = new RijndaelManaged();  
                rijndaelCipher.Key = Convert.FromBase64String(AesKey); // Encoding.UTF8.GetBytes(AesKey);  
                rijndaelCipher.IV = Convert.FromBase64String(AesIV);// Encoding.UTF8.GetBytes(AesIV);  
                rijndaelCipher.Mode = CipherMode.CBC;  
                rijndaelCipher.Padding = PaddingMode.PKCS7;  
                ICryptoTransform transform = rijndaelCipher.CreateDecryptor();  
                byte[] plainText = transform.TransformFinalBlock(encryptedData, 0, encryptedData.Length);  
                string result = Encoding.UTF8.GetString(plainText);  
                return result;  
            }  
            catch (Exception)  
            {  
                return null;  
            }  
        }  
        #endregion  
    }  
}