using Newtonsoft.Json;using System;using System.Collections.Generic;using System.Linq;using System.Net;using System.Threading.Tasks;namespace report.Utils{    public class WeChatHelper    {        public static string GetToken(string appId, string appSecret)        {            string tokenUrl = $"https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid={appId}&secret={appSecret}";            var wc = new WebClient();            var strReturn = wc.DownloadString(tokenUrl);            return strReturn;        }        //token缓存键值对        private static Dictionary
     
       tokenCache = new Dictionary
      
       ();        /// 
       
        /// 获取缓存令牌        /// 
        public static string GetAccessToken(string appid, string secret)        {            //token缓存            AccessToken result = null;            //判断缓存是否存在键：appid，就将缓存中的token赋给result            if (tokenCache.ContainsKey(appid))            {                result = tokenCache[appid];            }            //不存在则获取token            if (result == null)            {                result = JsonConvert.DeserializeObject
       
        (GetToken(appid, secret));                result.CreateTime = DateTime.Now;                tokenCache.Add(appid, result);            }            //判断是否在有效期内，过期重新获取token    给10s延迟时间            else if (System.DateTime.Compare(result.CreateTime.AddSeconds(result.Expires_In), System.DateTime.Now) < 10)            {                result = JsonConvert.DeserializeObject
        
         (GetToken(appid, secret));                result.CreateTime = DateTime.Now;                tokenCache[appid] = result;            }            return result.Access_token;        }    }    public class AccessToken    {        public string Access_token { get; set; }        public int Expires_In { get; set; }        public DateTime CreateTime { get; set; }    }}