asp.net开发微信公众平台之验证消息的真实性

/// <summary>
 /// 微信推送消息模型
 /// </summary>
 public class WeChatMsgRequestModel
 {
 public string timestamp { get; set; }
 public string nonce { get; set; }

 public string msg_signature { get; set; }
 }

public class WeChatRequestValidAttribute : ActionFilterAttribute
 {
 private const string Token = "StupidMe";

 public override void OnActionExecuting(ActionExecutingContext filterContext)
 {
 //参数适配
 Model.FormatModel.WeChatMsgRequestModel model = new Model.FormatModel.WeChatMsgRequestModel() { nonce= filterContext.HttpContext.Request.QueryString["nonce"],msg_signature= filterContext.HttpContext.Request.QueryString["msg_signature"],timestamp= filterContext.HttpContext.Request.QueryString["timestamp"] };
 //验证
 if (CheckSignature(model))
 {
 base.OnActionExecuting(filterContext);
 } 
 }

 private bool CheckSignature(Model.FormatModel.WeChatMsgRequestModel model)
 {
 string signature, timestamp, nonce, tempStr;
 //获取请求来的参数
 signature = model.msg_signature;
 timestamp = model.timestamp;
 nonce = model.nonce;
 //创建数组，将 Token, timestamp, nonce 三个参数加入数组
 string[] array = { Token, timestamp, nonce };
 //进行排序
 Array.Sort(array);
 //拼接为一个字符串
 tempStr = String.Join("", array);
 //对字符串进行 SHA1加密
 tempStr = FormsAuthentication.HashPasswordForStoringInConfigFile(tempStr, "SHA1").ToLower();
 //判断signature 是否正确
 if (tempStr.Equals(signature))
 {
 return true;
 }
 else
 {
 return false;
 }
 }
 }

/// <summary>
 /// 日志助手
 /// </summary>
 private static Common.LogHelper logger = new Common.LogHelper(typeof(HomeController));

 [Filters.WeChatRequestValid]
 public void Valid(Model.FormatModel.WeChatMsgRequestModel model)
 {
 if (ModelState.IsValid)
 {
 try
 {
 //判断是否是POST请求
 if (HttpContext.Request.HttpMethod.ToUpper() == "POST")
 {
 //从请求的数据流中获取请求信息
 using (Stream stream = HttpContext.Request.InputStream)
 {
 byte[] postBytes = new byte[stream.Length];
 stream.Read(postBytes, 0, (int)stream.Length);
 string postString = System.Text.Encoding.UTF8.GetString(postBytes);
 Handle(postString,model);
 }
 }
 }
 catch (Exception ex)
 {
 logger.Error("发生异常,异常信息：" + ex.Message + ex.StackTrace);
 }
 }
 }