using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Web;namespace WeiXinWebapplication{    public class CheckSignature    {        /// <summary>        /// 網站沒有提供Token情況下的默認Token        /// </summary>        public const string Token = "weixin";        /// <summary>        /// 檢查簽名是否正確        /// </summary>        /// <param name="signature">微信加密簽名</param>        /// <param name="timestamp">時間戳</param>        /// <param name="nonce">隨機數</param>        /// <param name="token"></param>        /// <returns></returns>        public static bool Check(string signature, string timestamp, string nonce, string token)        {            return signature == GetSignature(timestamp, nonce, token);        }        /// <summary>        /// 返回正確的簽名        /// </summary>        /// <param name="timestamp"></param>        /// <param name="nonce"></param>        /// <param name="token"></param>        /// <returns></returns>        public static string GetSignature(string timestamp, string nonce, string token = Token)        {            token = token ?? Token;            string[] arr = new[] {token,timestamp,nonce }.OrderBy(z=>z).ToArray();            string arrString = string.Join("",arr);            System.Security.Cryptography.SHA1 shal = System.Security.Cryptography.SHA1.Create();            byte[] shalArr = shal.ComputeHash(Encoding.UTF8.GetBytes(arrString));            StringBuilder enText = new StringBuilder();            foreach (var b in shalArr)            {                enText.AppendFormat("{0:x2}",b);            }            return enText.ToString();        }    }}

using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.UI;using System.Web.UI.WebControls;namespace WeiXinWebApplication{    public partial class Index : System.Web.UI.Page    {        /// <summary>        /// 與微信公眾賬號后臺的Token設置保持一致，區分大小寫        /// </summary>        PRivate readonly string Token = "weixin";        protected void Page_Load(object sender, EventArgs e)        {            Auth();        }        /// <summary>        /// 處理微信服務器驗證消息        /// </summary>        private void Auth()        {            string signature = Request["signature"];            string timestamp = Request["timestamp"];            string nonce = Request["nonce"];            string echostr = Request["echostr"];            if (Request.HttpMethod == "GET")            {                if (CheckSignature.Check(signature, timestamp, nonce, Token))                {                    WriteContent(echostr);                }                else                {                    WriteContent("failed:" + signature + "," + CheckSignature.GetSignature(timestamp, nonce, Token) + "." + "如果你在瀏覽器中看到這句話，說明此地址可以被作為微信公眾號后臺的URL,請注意保持Token一致。");                }                Response.End();            }        }        private void WriteContent(string str)        {            Response.Output.Write(str);        }    }}