将微信开放平台下的小程序应用与公众号通过openid进行关联操作

公司做的是第三方开放平台，为了使用户的小程序信息与公众号信息关联起来（通过openid关联）

不考虑使用将公众号与小程序绑定在同一个开放平台下，通过获取UnionID 机制（开放平台下可绑定账号受限，只有50个），不适应公司几千商户的应用场景

第一步 在小程序里使用 web-view 来嵌套H5授权地址，得把小程序openid加在授权页面

<web-view src='{{web_url}}'>

</web-view>

  /**
   * 页面的初始数据
   */
  data: {
    web_url: ''
  },

  /**
   * 生命周期函数--监听页面加载
   */
  onLoad: function(options) {
    this.setData({
      web_url: app.globalData.wxgh_oauth_url + '/Wxgh/Index?openid=' + app.globalData.openid
    });
    console.log(this.data.web_url);
  },

第二步 处理第一步的页面路径，将页面参数拼接好，再去调用C# 写的拼接授权路径，

<body>
    <input type="hidden" id="hiddenBaseUrl" value="@ViewBag.BaseUrl" />

    <div class="error">

    </div>
    <div class="go-wxapp">
        <button type="button" id="btn" class="go-wxapp-btn"> 返回老板助手</button>
    </div>
</body>
</html>

<script>
    $(function () {
        $('.go-wxapp').hide();
        getAuthorizeUrl();
    })
    $('#btn').click(function () {
        wx.miniProgram.switchTab({
            url: '/pages/index/index'
        });
    });
    function getUrlParam(name) {
        var reg = new RegExp("(^|&)" + name + "=([^&]*)(&|$)"); //构造一个含有目标参数的正则表达式对象
        var r = window.location.search.substr(1).match(reg);  //匹配目标参数
        if (r != null) return unescape(r[2]); return null; //返回参数值
    }

    function getAuthorizeUrl() {

        var url = $('#hiddenBaseUrl').val();

        $.ajax({
            type: 'get',
            url: url + '/api/services/app/WxghService/GetAuthorizeUrl?wxapp_openid=' + getUrlParam('openid'),
            data: {},
            success: (res) => {
                console.log('获取授权链接');
                console.log(res);
                if (res.success) {
                    var _result = res.result;
                    if (_result.success) {
                        if (_result.code == 2000) {//已关注
                            wx.miniProgram.switchTab({
                                url: '/pages/index/index'
                            });
                        } else {
                            window.location.href = _result.data;
                        }

                    } else {

                        $('.error').html("异常，因为：" + _result.message);
                        $('.go-wxapp').show();

                    }
                    // window.location.href = res.result;
                } else {
                    alert("授权异常，请返回");
                }
            }
        });
    }

</script>

C# 提供接口获取公众号授权地址

微信接口

代码中 OAuthApi.GetAuthorizeUrl 方法是对下面地址的封装

https://open.weixin.qq.com/connect/oauth2/authorize?appid=APPID&redirect_uri=REDIRECT_URI&response_type=code&scope=SCOPE&state=STATE#wechat_redirect

  #region 拼接授权链接地址
        public async Task<Result> GetAuthorizeUrl(string wxapp_openid)
        {
            var _result = new Result();

            try
            {
                if (string.IsNullOrWhiteSpace(wxapp_openid))
                {
                    _result.success = false;
                    _result.message = "关联小程序参数为空";
                    return _result;
                }
                var user = await _wxappUserRepository.GetAllListAsync(a => a.openid == wxapp_openid.Trim());
                if (user.Count == 0)
                {
                    _result.success = false;
                    _result.message = "请从小程序进入";
                    return _result;
                } var wxghUserRelation = await _wxghUserRelationRepository.FirstOrDefaultAsync(a => a.wxapp_openid == wxapp_openid.Trim());
                if (wxghUserRelation != null)
                {                
                    _result.success = true;
                    _result.message = "已关联公众号";
                    _result.code = (int)ResultCodeEnum.已关联公众号;
                    return _result;
                }


                var redirectUrl = base_url + "Wxgh/WxAuthorize?wxapp_openid=" + wxapp_openid.Trim();
                _result.data = OAuthApi.GetAuthorizeUrl(wxghAppid, redirectUrl, "boss", OAuthScope.snsapi_base);
                _result.success = true;
            }
            catch (Exception ex)
            {
                _result.success = false;
                _result.message = ex.Message;
            }

            return _result;
        }
        #endregion

code换取openid，并将小程序openid与公众号openid绑定

<head>
    <meta name="viewport" content="width=device-width" />
    <meta charset="UTF-8"> <!-- for HTML5 -->
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <script src="~/JavaScript/jquery-3.4.1.min.js"></script>
    <script src="https://res.wx.qq.com/open/js/jweixin-1.4.0.js"></script>
    <title>绑定公众号</title>
</head>
<body>
    <div class="error">
        @_result
    </div>
    @if (!string.IsNullOrWhiteSpace(_result))
    {
        <div class="go-wxapp">
            <button type="button" id="btn" class="go-wxapp-btn"> 返回老板助手</button>
        </div>
    }
</body>
</html>
<script>
    $('#btn').click(function () {
        wx.miniProgram.switchTab({
            url: '/pages/index/index'
        });
    });

</script>

public IActionResult WxAuthorize(string code, string state, string wxapp_openid)
        {
            Logger.ErrorFormat("code={0}  state={1} wxapp_openid={2}", code, state, wxapp_openid);
            try
            {
                if (string.IsNullOrWhiteSpace(code))
                {
                    ViewBag.Result = "异常，参数CODE为空，请点击返回老板助手";
                    return View();

                }
                code = code.Trim();
                if (string.IsNullOrWhiteSpace(state))
                {
                    ViewBag.Result = "异常，参数STATE为空,请点击返回老板助手";
                    return View();
                }
                state = state.Trim();
                if (string.IsNullOrWhiteSpace(wxapp_openid))
                {
                    ViewBag.Result = "异常，参数小程序ID为空,请点击返回老板助手";
                    return View();
                }
                wxapp_openid = wxapp_openid.Trim();
                var accessToken = Senparc.Weixin.MP.AdvancedAPIs.OAuthApi.GetAccessToken(wxghAppid, wxghAppSecret, code);
                if (accessToken.errcode != 0)
                {
                    ViewBag.Result = "错误代码：" + accessToken.errcode + " 说明：" + accessToken.errmsg + ",请点击返回老板助手";
                    return View();
                }
                var wxghUser = _wxghUserRelationRepository.FirstOrDefault(a => a.wxapp_openid == wxapp_openid);
                if (wxghUser != null)
                {
                    ViewBag.Result = "已关联公众号，请点击返回老板助手";
                    return View();

                }
                wxghUser = _wxghUserRelationRepository.FirstOrDefault(a => a.wxgh_openid == accessToken.openid);
                if (wxghUser != null)
                {
                    ViewBag.Result = "您已关联公众号，请点击返回老板助手";
                    return View();
                }

                wxghUser = new wxgh_user_relation()
                {
                    access_token = accessToken.access_token,
                    bind_date = DateTime.Now,
                    expires_in = DateTime.Now.AddSeconds(accessToken.expires_in),
                    refresh_token = accessToken.refresh_token,
                    wxapp_openid = wxapp_openid,
                    wxgh_openid = accessToken.openid
                };
 _wxghUserRelationRepository.Insert(wxghUser);
                CurrentUnitOfWork.SaveChanges();
                ViewBag.Result = "绑定成功，请点击返回老板助手";
                return View();
            }
            catch (Exception ex)
            {
                ViewBag.Result = "异常，" + ex.Message + ",请点击返回老板助手";
                return View();
            }

        }

代码里使用了.NET ABP 、盛派公司的盛派微信SDK

原文地址：https://www.cnblogs.com/WQ1992/p/12937772.html