public class WeChatRequestModel
    {
        public string signature { get; set; }
        public string timestamp { get; set; }
        public string nonce { get; set; }
        public string echostr { get; set; }
    }

          /// <summary>
        /// 定義Token，與微信公共平臺(tái)上的Token保持一致
        /// </summary>
 private const string Token = "StupidMe";
   public void Valid(WeChatRequestModel model)
        {
            //獲取請(qǐng)求來(lái)的 echostr 參數(shù)
            string echoStr = model.echostr;
            //通過驗(yàn)證，出于安全考慮。（也可以跳過）
            if (CheckSignature(model))
            {
                if (!string.IsNullOrEmpty(echoStr))
                {
                    //將隨機(jī)生成的 echostr 參數(shù) 原樣輸出
                    Response.WriteAsync(echoStr);
                    //截止輸出流
                    //Response.end();
                }
            }
        }

/// <summary>
        /// 驗(yàn)證簽名，檢驗(yàn)是否是從微信服務(wù)器上發(fā)出的請(qǐng)求
        /// </summary>
        /// <param name="model">請(qǐng)求參數(shù)模型 Model</param>
        /// <returns>是否驗(yàn)證通過</returns>
        private bool CheckSignature(WeChatRequestModel model)
        {
            string signature, timestamp, nonce, tempStr;
            //獲取請(qǐng)求來(lái)的參數(shù)
            signature = model.signature;
            timestamp = model.timestamp;
            nonce = model.nonce;
            //創(chuàng)建數(shù)組，將 Token, timestamp, nonce 三個(gè)參數(shù)加入數(shù)組
            string[] array = { Token, timestamp, nonce };
            //進(jìn)行排序
            Array.Sort(array);
            //拼接為一個(gè)字符串
            tempStr = String.Join("", array);
            //對(duì)字符串進(jìn)行 SHA1加密
            tempStr = Get_SHA1_Method2(tempStr);
            //判斷signature 是否正確
            if (tempStr.Equals(signature))
            {
                return true;
            }
            else
            {
                return false;
            }
        }

 public string Get_SHA1_Method2(string strSource)
        {
            string strResult = "";
            //Create 
            System.Security.Cryptography.SHA1 md5 = System.Security.Cryptography.SHA1.Create();
            //注意編碼UTF8、UTF7、Unicode等的選擇 
            byte[] bytResult = md5.ComputeHash(System.Text.Encoding.UTF8.GetBytes(strSource));
            //字節(jié)類型的數(shù)組轉(zhuǎn)換為字符串 
            for (int i = 0; i < bytResult.Length; i++)
            {
                //16進(jìn)制轉(zhuǎn)換 
                strResult = strResult + bytResult[i].ToString("X");
            }
            return strResult.ToLower();
        }