前言

微信相關配置請參考 微信公眾平臺 的這篇文章。注意授權回撥域名一定要修改正確。

微信網頁授權是通過OAuth2.0機制實現的，所以我們可以使用 https://github.com/china-live/QQConnect 這個開源專案提供的中介軟體來實現微信第三方登入的流程。

開發流程

1、新建一個.net core webapi 專案。在NuGet中查詢並安裝 AspNetCore.Authentication.WeChat 包。

2、修改 appsettings.json 配置檔案，增加以下配置：

 1 "Authentication": {
 2     "WeChat": {
 3       "AppId": "微信AppID",
 4       "AppSecret": "微信AppSecret"
 5     }
 6   },
 7   "Logging": {
 8     "LogLevel": {
 9       "Default": "Debug", //日誌級別從低到高，依次為：Debug,Information,Warning,Error,None
10       "Microsoft.EntityFrameworkCore": "Error",
11       "System": "Error"
12     }
13   }

3、修改 Startup

1 services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
2         services.AddAuthentication()
3                 .AddWeChat(wechatOptions =>
4                 {
5                     wechatOptions.AppId = Configuration["Authentication:WeChat:AppId"];
6                     wechatOptions.AppSecret = Configuration["Authentication:WeChat:AppSecret"];
7                     wechatOptions.UseCachedStateDataFormat = true;
8                 });

4、新增 AccountController

 1 [Route("api/[controller]")]
 2     [ApiController]
 3     public class AccountController : ControllerBase
 4     {
 5         private const string LoginProviderKey = "LoginProvider";
 6         private const string Provider_WeChat = "WeChat";
 7         private readonly ILogger _logger;
 8         private readonly IHttpContextAccessor _contextAccessor;
 9 
10         public AccountController(ILogger<AccountController> logger,
11             IHttpContextAccessor contextAccessor)
12         {
13             _logger = logger;
14             _contextAccessor = contextAccessor;
15         }
16         /// <summary>
17         /// 微信登入
18         /// </summary>
19         /// <param name="redirectUrl">授權成功後的跳轉地址</param>
20         /// <returns></returns>
21         [HttpGet("LoginByWeChat")]
22         public IActionResult LoginByWeChat(string redirectUrl)
23         {
24             var request = _contextAccessor.HttpContext.Request;
25             var url = $"{request.Scheme}://{request.Host}{request.PathBase}{request.Path}Callback?provider={Provider_WeChat}&redirectUrl={redirectUrl}";
26             var properties = new AuthenticationProperties { RedirectUri = url };
27             properties.Items[LoginProviderKey] = Provider_WeChat;
28             return Challenge(properties, Provider_WeChat);
29         }
30         /// <summary>
31         /// 微信授權成功後自動回撥的地址
32         /// </summary>
33         /// <param name="provider"></param>
34         /// <param name="redirectUrl">授權成功後的跳轉地址</param>
35         /// <returns></returns>
36         [HttpGet("LoginByWeChatCallback")]
37         public async Task<IActionResult> LoginByWeChatCallbackAsync(string provider = null, string redirectUrl = "")
38         {
39             var authenticateResult = await _contextAccessor.HttpContext.AuthenticateAsync(provider);
40             if (!authenticateResult.Succeeded) return Redirect(redirectUrl);
41             var openIdClaim = authenticateResult.Principal.FindFirst(ClaimTypes.NameIdentifier);
42             if (openIdClaim == null || openIdClaim.Value.IsNullOrWhiteSpace())
43                 return Redirect(redirectUrl);
44             //TODO 記錄授權成功後的微信資訊 
45             var city = authenticateResult.Principal.FindFirst("urn:wechat:city")?.Value;
46             var country = authenticateResult.Principal.FindFirst(ClaimTypes.Country)?.Value;
47             var headimgurl = authenticateResult.Principal.FindFirst(ClaimTypes.Uri)?.Value;
48             var nickName = authenticateResult.Principal.FindFirst(ClaimTypes.Name)?.Value;
49             var openId = authenticateResult.Principal.FindFirst(ClaimTypes.NameIdentifier)?.Value;
50             var privilege = authenticateResult.Principal.FindFirst("urn:wechat:privilege")?.Value;
51             var province = authenticateResult.Principal.FindFirst("urn:wechat:province")?.Value;
52             var sexClaim = authenticateResult.Principal.FindFirst(ClaimTypes.Gender);
53             int sex = 0;
54             if (sexClaim != null && !sexClaim.Value.IsNullOrWhiteSpace())
55                 sex = int.Parse(sexClaim.Value);
56             var unionId = authenticateResult.Principal.FindFirst("urn:wechat:unionid")?.Value;
57             _logger.LogDebug($"WeChat Info=> openId: {openId},nickName: {nickName}");
58             return Redirect($"{redirectUrl}?openId={openIdClaim.Value}");
59         }
60     }

5、將網站釋出到外網，請求

1 https://你的授權域名/api/account/LoginByWeChat?redirectUrl=授權成功後要跳轉的頁面

即可調起微信授權頁面。

注意

微信授權必須使用https

微信開放平臺和微信公眾平臺都有提供網站用微信登入的介面，前者適用於任何網站，後者只適用於微信服務號的內嵌網站

本篇相關原始碼地址：https://github.com/ren8179/QrF.OAuth.WeChat/tree/ma