WeChatAuthorizedLoginDemo_微信授权登录DEMO

【核心代码】

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using Newtonsoft.Json;

/// <summary>
/// WeiXin 的摘要说明
/// </summary>
public abstract class WeiXinPage : System.Web.UI.Page, System.Web.SessionState.IRequiresSessionState
{
    protected sealed override void OnPreInit(EventArgs e)
    {
        if (isGuest)
        {
            getWxUser();
        }
        base.OnPreInit(e);
    }
    /// <summary>
    /// 是否访客身份 true:是 false:否
    /// </summary>
    public static bool isGuest
    {
        get
        {
            return HttpContext.Current.Session[_user] == null ? true : false;
        }
    }
    private static string _user { get { return "$wxuser"; } }
    private static string _code { get { return "$wxcode"; } }
    private static string _AbsoluteUri { get { return HttpContext.Current.Request.Url.AbsoluteUri; } }
    /// <summary>
    /// 该路径剔除微信Query的URL用于页面重定向获取最新的用户信息
    /// </summary>
    private static string _RawUrl
    {
        get
        {
            string url = HttpContext.Current.Request.Url.AbsoluteUri;
            url = url.Replace(url.Substring(url.IndexOf("code"), url.IndexOf("STATE")   5 - url.IndexOf("code")), "");
            return url;
        }
    }
    /// <summary>
    /// 获取微信用户信息
    /// </summary>
    private static Dictionary<string, object> getWxUser()
    {
        string code = HttpContext.Current.Request.QueryString.Get("code") ?? "",
               url = "",
               ret = "";
        try
        {
            object user = HttpContext.Current.Session[_user];
            if (code.Length == 0 && user == null)
            {
                JumpUrl();
                return null;
            }
            if (user != null) return JsonConvert.DeserializeObject<Dictionary<string, object>>(HttpContext.Current.Session[_user].ToString());
            #region /*如果session中不存在user信息则对接微信接口获取用户信息*/
            /* 根据code获取access_token */
            url = string.Format("https://api.weixin.qq.com/sns/oauth2/access_token?appid={0}&secret={1}&code={2}&grant_type=authorization_code"
                           , Config.AppId
                           , Config.AppSecret
                           , code);
            ret = HttpService.Get(url);
            Dictionary<string, string> o = JsonConvert.DeserializeObject<Dictionary<string, string>>(ret);
            #region 注意处理微错误{"errcode":40163, "errmsg":"code been used"} 以及{"errcode":40029, "errmsg":"invalid code"}
            if (o.ContainsKey("errmsg"))
            {
                if (o["errcode"] == "40163" || o["errcode"] == "40029")
                {
                    HttpContext.Current.Response.Redirect(_RawUrl, false);
                    return null;
                }
                throw new Exception(o["errmsg"]);
            }
            #endregion
            /* 根据access_token和openid获取用户信息 */
            url = string.Format("https://api.weixin.qq.com/sns/userinfo?access_token={0}&openid={1}&lang=zh_CN"
                                , o["access_token"]
                                , o["openid"]);
            ret = HttpService.Get(url);
            /*保存用户到Session*/
            HttpContext.Current.Session[_user] = ret;
            #endregion
            return JsonConvert.DeserializeObject<Dictionary<string, object>>(HttpContext.Current.Session[_user].ToString());
        }
        catch
        {
            throw;
        }
    }
    /// <summary>
    /// 跳转至微信授权登录页
    /// </summary>
    private static void JumpUrl()
    {
        string url = string.Format("https://open.weixin.qq.com/connect/oauth2/authorize?appid={0}&redirect_uri={1}&response_type=code&scope=snsapi_userinfo&state=STATE#wechat_redirect"
                                  , Config.AppId
                                  , _AbsoluteUri);
        HttpContext.Current.Response.Redirect(url, false);
    }

    /// <summary>
    /// 微信用户信息
    /// </summary>
    public Dictionary<string, object> Data
    {
        get
        {
            return getWxUser();
        }
    }
}