public class weixin_helper
 {
  public weixin_helper()
  {
  }
  /// <summary>
  /// 根据AppID和AppSecret获得access token(默认过期时间为2小时)
  /// </summary>
  /// <returns>Dictionary</returns>
  public static Dictionary<string, object> get_access_token()
  {
   //获得配置信息
   oauth_config config = oauth_helper.get_config(2);
   string send_url = \"https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=\" +
        config.oauth_app_id + \"&secret=\" + config.oauth_app_key + \"\";
   //发送并接受返回值
   string result = Utils.HttpGet(send_url);
   if (result.Contains(\"errmsg\"))
   {
    return null;
   }
   try
   {
    Dictionary<string, object> dic = JsonConvert.DeserializeObject<Dictionary<string, object>>(result);
    return dic;
   }
   catch
   {
    return null;
   }
  } /// <summary>
  /// 取得临时的Access Token(默认过期时间为2小时)
  /// </summary>
  /// <param name=\"code\">临时Authorization Code</param>
  /// <param name=\"state\">防止CSRF攻击，成功授权后回调时会原样带回</param>
  /// <returns>Dictionary</returns>
  public static Dictionary<string, object> get_access_token(string code, string state)
  {
   //获得配置信息
   oauth_config config = oauth_helper.get_config(2);
   string send_url = \"https://api.weixin.qq.com/sns/oauth2/access_token?appid=\" +
        config.oauth_app_id + \"&secret=\" + config.oauth_app_key + \"&code=\"+code+\"&grant_type=authorization_code\";
   //发送并接受返回值
   string result = Utils.HttpGet(send_url);
   if (result.Contains(\"errmsg\"))
   {
    return null;
   }
   try
   {
    Dictionary<string, object> dic = JsonConvert.DeserializeObject<Dictionary<string, object>>(result);
    return dic;
   }
   catch
   {
    return null;
   }
  }
  /// <summary>
  /// 根据access_token判断access_token是否过期
  /// </summary>
  /// <param name=\"access_token\"></param>
  /// <returns>true表示未失效</returns>
  public static bool check_access_token(string access_token)
  {
   //获得配置信息
   oauth_config config = oauth_helper.get_config(2);
   string send_url = \"https://api.weixin.qq.com/sns/auth?access_token=\" + access_token + \"&openid=\" + config.oauth_app_id;
   //发送并接受返回值
   string result = Utils.HttpGet(send_url);
   try
   {
    Dictionary<string, object> dic = JsonConvert.DeserializeObject<Dictionary<string, object>>(result);
    if (dic.ContainsKey(\"errmsg\"))
    {
     if (dic[\"errmsg\"].ToString()==\"ok\")
     {
      return true;
     }
     else
     {
      return false;
     }
    }
    return false;
   }
   catch
   {
    return false;
   }
  }
  /// <summary>
  /// 若fresh_token已过期则根据refresh_token取得新的refresh_token
  /// </summary>
  /// <param name=\"refresh_token\">refresh_token</param>
  /// <returns>Dictionary</returns>
  public static Dictionary<string, object> get_refresh_token(string refresh_token)
  {
   //获得配置信息
   oauth_config config = oauth_helper.get_config(2);
   string send_url =
    \"https://api.weixin.qq.com/sns/oauth2/refresh_token?appid=\" +
        config.oauth_app_id + \"&grant_type=refresh_token&refresh_token=\" + refresh_token;
   //发送并接受返回值
   string result = Utils.HttpGet(send_url);
   if (result.Contains(\"errmsg\"))
   {
    return null;
   }
   try
   {
    Dictionary<string, object> dic = JsonConvert.DeserializeObject<Dictionary<string, object>>(result);
    return dic;
   }
   catch
   {
    return null;
   }
  }
  /// <summary>
  /// 获取登录用户自己的基本资料
  /// </summary>
  /// <param name=\"access_token\">临时的Access Token</param>
  /// <param name=\"open_id\">用户openid</param>
  /// <returns>Dictionary</returns>
  public static Dictionary<string, object> get_user_info(string access_token, string open_id)
  {
   //获得配置信息
   oauth_config config = oauth_helper.get_config(2);
   //发送并接受返回值 
   string send_url = \"https://api.weixin.qq.com/sns/userinfo?access_token=\"+access_token+\"&openid=\"+open_id;
   //发送并接受返回值
   string result = Utils.HttpGet(send_url);
   if (result.Contains(\"errmsg\"))
   {
    return null;
   }
   //反序列化JSON
   Dictionary<string, object> dic = JsonHelper.DataRowFromJSON(result);
   return dic;
  }
 }

#region 微信登录
  /// <summary>
  /// 微信登录
  /// </summary>
  public ActionResult WeChat()
  {
   //获得配置信息
   oauth_config config = oauth_helper.get_config(2); //主键id
   if (config == null)
   {
    return Content(\"出错了，您尚未配置微信相关的API信息！\");
   }
   string state = Guid.NewGuid().ToString().Replace(\"-\", \"\");
   Session[\"oauth_state\"] = state;
   string send_url =
    \"https://open.weixin.qq.com/connect/qrconnect?appid=\" + config.oauth_app_id +
        \"&redirect_uri=\" + Utils.UrlEncode(config.return_uri.ToLower()) +
        \"&response_type=code&scope=snsapi_login&state=\" + state +
        \"#wechat_redirect\";
   //开始发送
   return Redirect(send_url); //跳转到微信自己 指定的关联登陆页面
  }
  /// <summary>
  /// 微信登录返回action
  /// </summary>
  public ActionResult WeChatReturnUrl(string state, string code)
  {
   //取得返回参数
   string access_token = string.Empty;
   string expires_in = string.Empty;
   string client_id = string.Empty;
   string openid = string.Empty;
   string refresh_token = string.Empty;
   if (Session[\"oauth_state\"] == null || Session[\"oauth_state\"].ToString() == \"\" ||
    state != Session[\"oauth_state\"].ToString() || string.IsNullOrEmpty(code))//若返回参数中未包含code或者state没有通过验证则提示出错
   {
    return Content(\"出错啦，state未初始化！\");
   }
   //第一步：通过code来获取Access Token以及openid
   Dictionary<string, object> dic1 = weixin_helper.get_access_token(code, state);
   if (dic1 == null || !dic1.ContainsKey(\"access_token\"))
   {
    return Content(\"错误代码：，无法获取Access Token，请检查App Key是否正确！\");
   }
   if (dic1 == null || !dic1.ContainsKey(\"openid\"))
   {
    if (dic1.ContainsKey(\"errmsg\"))
    {
     return Content(\"errcode：\" + dic1[\"errcode\"] + \",errmsg：\" + dic1[\"errmsg\"]);
    }
    else
    {
     return Content(\"出错啦，无法获取用户授权Openid！\");
    }
   }
   access_token = dic1[\"access_token\"].ToString();//获取access_token
   expires_in = dic1[\"expires_in\"].ToString();//获取过期时间
   refresh_token = dic1[\"refresh_token\"].ToString();//获取用于重新刷新access_token的凭证
   openid = dic1[\"openid\"].ToString();//用户唯一标示openid
   //储存获取数据用到的信息
   Session[\"oauth_name\"] = \"webchat\";
   Session[\"oauth_access_token\"] = access_token;
   Session[\"oauth_openid\"] = openid;
   Session[\"oauth_refresh_token\"] = refresh_token;
   #region todo 将获取到的用户信息保存到数据库中
   #endregion
   //第二步：通过Access Token以及openid来获取用户的基本信息
   //Dictionary<string, object> dic2 = weixin_helper.get_user_info(access_token,openid);
   //第三步：跳转到指定页面
   return Content(WeChatResultJson());
  }
  /// <summary>
  /// 微信登录返回action, 处理用户信息
  /// </summary>
  public string WeChatResultJson()
  {
   string oauth_access_token = string.Empty;
   string oauth_openid = string.Empty;
   string oauth_name = string.Empty;
   string oauth_refresh_token = string.Empty;
   if (Session[\"oauth_name\"] == null || Session[\"oauth_access_token\"] == null ||
    Session[\"oauth_openid\"] == null)
   {
    return \"{\\\"ret\\\":\\\"1\\\", \\\"msg\\\":\\\"出错啦，Access Token已过期或不存在！\\\"}\";
   }
   oauth_name = Session[\"oauth_name\"].ToString();
   oauth_access_token = Session[\"oauth_access_token\"].ToString();
   oauth_openid = Session[\"oauth_openid\"].ToString();
   oauth_refresh_token = Session[\"oauth_refresh_token\"].ToString();
   if (!weixin_helper.check_access_token(oauth_access_token)) //调用access_token前需判断是否过期
   {
    Dictionary<string, object> dic1 = weixin_helper.get_refresh_token(oauth_refresh_token);//如果已过期则重新换取新的access_token
    if (dic1 == null || !dic1.ContainsKey(\"access_token\"))
    {
     return \"{\\\"openid\\\":\\\"0\\\", \\\"msg\\\":\\\"出错啦，无法获取access_token！\\\"}\";
    }
    oauth_access_token = dic1[\"access_token\"].ToString();
   }
   Dictionary<string, object> dic = weixin_helper.get_user_info(oauth_access_token, oauth_openid);
   if (dic == null)
   {
    return \"{\\\"openid\\\":\\\"0\\\", \\\"msg\\\":\\\"出错啦，无法获取授权用户信息！\\\"}\";
   }
   try
   {
    StringBuilder str = new StringBuilder();
    str.Append(\"{\");
    str.Append(\"\\\"openid\\\": \\\"\" + dic[\"openid\"].ToString() + \"\\\", \");
    str.Append(\"\\\"nickname\\\": \\\"\" + dic[\"nickname\"].ToString() + \"\\\", \");
    str.Append(\"\\\"sex\\\": \\\"\" + dic[\"sex\"].ToString() + \"\\\", \");
    str.Append(\"\\\"province\\\": \\\"\" + dic[\"province\"].ToString() + \"\\\", \");
    str.Append(\"\\\"city\\\": \\\"\" + dic[\"city\"].ToString() + \"\\\", \");
    str.Append(\"\\\"country\\\": \\\"\" + dic[\"country\"].ToString() + \"\\\", \");
    str.Append(\"\\\"headimgurl\\\": \\\"\" + dic[\"headimgurl\"].ToString() + \"\\\", \");
    str.Append(\"\\\"privilege\\\": \\\"\" + dic[\"privilege\"].ToString() + \"\\\", \");
    str.Append(\"\\\"unionid\\\": \\\"\" + dic[\"unionid\"].ToString() + \"\\\"\");
    str.Append(\"\\\"oauth_name\\\": \\\"\" + oauth_name + \"\\\"\");
    str.Append(\"\\\"oauth_access_token\\\": \\\"\" + oauth_access_token + \"\\\"\");
    str.Append(\"\\\"oauth_openid\\\": \\\"\" + oauth_openid + \"\\\"\");
    str.Append(\"}\");
    return str.ToString();
   }
   catch
   {
    return \"{\\\"ret\\\":\\\"0\\\", \\\"msg\\\":\\\"出错啦，无法获取授权用户信息！\\\"}\";
   }
  }
  #endregion