童鞋们直接看代码吧：（我这里是ashx处理程序写的类，开发过网站的一般都知道）
<%@ WebHandler Language="C#" class="weixin" %>
using System;using System.Web;using System.IO;using System.Text;using System.Security.Cryptography;using System.Security.Policy;using System.Collections;using System.Xml;public class weixin : IHttpHandler { protected string TOKEN = "asdasd"; //TOKEN 必须跟你在微信公众平台上写的token是一致的 public void ProcessRequest (HttpContext context) { //context.Response.ContentType = "text/plain"; context.Response.Clear(); //清除所有之前生成的Response内容 Handlewinxin(context); //进入专业微信处理程序 context.Response.End(); } public bool IsReusable { get { return false; } } /// <summary> /// /// </summary> /// <param name="content"></param> public void Handlewinxin(HttpContext context) { if (context.Request.HttpMethod.ToUpper() == "GET") { // 微信加密签名 string signature = context.Request.QueryString["signature"]; // 时间戳 string timestamp = context.Request.QueryString["timestamp"]; // 随机数 string nonce = context.Request.QueryString["nonce"]; // 随机字符串 string echostr = context.Request.QueryString["echostr"]; if (CheckSignature(signature, timestamp, nonce)) { context.Response.Write(echostr); } } else if (context.Request.HttpMethod.ToUpper() == "POST") { StreamReader stream = new StreamReader(context.Request.InputStream); string xml = stream.ReadToEnd(); processRequest(xml, context); } } /// <summary> /// 验证签名 /// </summary> /// <param name="signature"></param> /// <param name="timestamp"></param> /// <param name="nonce"></param> /// <returns></returns> public bool CheckSignature(String signature, String timestamp, String nonce) { String[] arr = new String[] { TOKEN, timestamp, nonce }; // 将token、timestamp、nonce三个参数进行字典序排序 Array.Sort<String>(arr); StringBuilder content = new StringBuilder(); for (int i = 0; i < arr.Length; i++) { content.Append(arr[i]); } String tmpStr = SHA1_Encrypt(content.ToString()); // 将sha1加密后的字符串可与signature对比，标识该请求来源于微信 return tmpStr != null ? tmpStr.Equals(signature) : false; } /// <summary> /// 使用缺省密钥给字符串加密 /// </summary> /// <param name="Source_String"></param> /// <returns></returns> public static string SHA1_Encrypt(string Source_String) { byte[] StrRes = Encoding.Default.GetBytes(Source_String); HashAlgorithm iSHA = new SHA1CryptoServiceProvider(); StrRes = iSHA.ComputeHash(StrRes); StringBuilder EnText = new StringBuilder(); foreach (byte iByte in StrRes) { EnText.AppendFormat("{0:x2}", iByte); } return EnText.ToString(); } /// <summary> /// 处理微信发来的请求 /// </summary> /// <param name="xml"></param> public void processRequest(String xml,HttpContext context) { //待下一章节全部贴出代码 }}