C# 调用微信公众号接口生成带参数二维码、下载、合并

朴灿烈づ我的快乐病毒、 2022-06-02 00:53 319阅读 0赞

**一、生成带参数二维码**

官方文档：[https://mp.weixin.qq.com/wiki?t=resource/res\_main&id=mp1443433542][https_mp.weixin.qq.com_wiki_t_resource_res_main_id_mp1443433542]

**1.请求地址**

/// <summary>
    /// 创建二维码--Post
    /// </summary>
    /// <returns></returns>
    public string GetQrCode()
    {
        string url = string.Format("https://api.weixin.qq.com/cgi-bin/qrcode/create?access_token={0}", config.Access_Token);
        return url;
    }

**2.使用POST提交获取ticket 和链接地址**

/// <summary>
    /// 创建二维码-带有推荐人的openid
    /// </summary>
    /// <param name="fromuser"></param>
    /// <returns></returns>
    public string Create(string fromuser)
    {
        string url = new LinkManage().GetQrCode();
        JObject data = new JObject();
        data.Add("action_name", "QR_LIMIT_STR_SCENE");
        data.Add("action_info", JObject.FromObject(new
        {
            scene = new
            {
                scene_str = fromuser
            }
        }));
        string result = NetHelper.Post(url, data.ToString());
        JObject back = JObject.Parse(result);
        JToken ticket = back.SelectToken("ticket");
        if (ticket == null)
            throw new Exception($"获取二维码失败：" + result);
        return ticket.ToString();
    }

**3.根据ticket获取二维码图片 ，就是一个地址**

/// <summary>
    /// 获取二维码图片
    /// </summary>
    /// <param name="ticket"></param>
    /// <returns></returns>
    public string GetQrCodeShow(string ticket)
    {
        string url = string.Format("https://mp.weixin.qq.com/cgi-bin/showqrcode?ticket={0}"
            , SecurityHelper.UrlEncode(ticket));
        return url;
    }

**二、下载二维码到本地**

/// <summary>
    /// 下载二维码图片
    /// </summary>
    /// <param name="fromuser"></param>
    /// <returns></returns>
    public string Download(string fromuser)
    {
        //1.创建
        string ticket = Create(fromuser);
        //2.下载
        string url = new LinkManage().GetQrCodeShow(ticket);
        string filename = $"{fromuser}.jpg";
        string path = AppDomain.CurrentDomain.BaseDirectory + "data/wxqrcode/" + filename;
        //如果已经存在删除
        if (File.Exists(path))
            File.Delete(path);
        //下载
        DownFile(url, path);
        return path;
    }

使用WebClient下载文件：

//下载到文件
    public static void DownFile(string url, string target)
    {
        try
        {
            WebClient _client = new WebClient();
            byte[] data = _client.DownloadData(url);
            File.WriteAllBytes(target, data);
        }
        catch (Exception ex)
        {
            throw new Exception("下载文件(" + target + ")失败：" + ex.Message + "|" + ex.StackTrace);
        }
    }

**三、合成二维码到海报图片**

注：C\#使用GDI+ 合成图片

/// <summary>
    /// 生成推荐海报,返回图片地址
    /// </summary>
    /// <param name="user"></param>
    public string MergeImage(OAuthUser user)
    {
        //1.下载二维码
        string qrcode = Download(user.openid);
        //2.下载头像
        string touxiang = AppDomain.CurrentDomain.BaseDirectory + "data/wxtx/" + user.openid + ".jpg";
        if (File.Exists(touxiang))
            File.Delete(touxiang);
        DownFile(user.headimgurl, touxiang);
    
        //3.合成到一张图片
        string resultfile = AppDomain.CurrentDomain.BaseDirectory + "data/share/" + user.openid + ".jpg";
    
        string bgfile = AppDomain.CurrentDomain.BaseDirectory + "assets/pages/img/qrcode.jpg";
        Bitmap bit = new Bitmap(bgfile, false);
        Graphics g = Graphics.FromImage(bit);
    
        //添加二维码
        Bitmap qrcodeImage = new Bitmap(qrcode);
        g.DrawImage(qrcodeImage, 540, 1155, 180, 180);
    
        //添加头像 
        Bitmap touxiangImage = new Bitmap(touxiang);
        g.DrawImage(touxiangImage, 10, 10, 80, 80);
        //添加昵称
        g.DrawString(user.nickname, new Font("微软雅黑", 10, FontStyle.Regular), Brushes.White, 100, 25);
        g.Dispose();
        //保存
        bit.Save(resultfile, ImageFormat.Jpeg);
        bit.Dispose();
        qrcodeImage.Dispose();
        touxiangImage.Dispose();
    
        return resultfile;
    }

[C\# 使用curl工具 上传图片到微信服务器示例][C_ _curl_]

[curl工具使用简介][curl]

[如何判断微信内置浏览器(JS & .Net)][JS _ .Net]

[https_mp.weixin.qq.com_wiki_t_resource_res_main_id_mp1443433542]: https://mp.weixin.qq.com/wiki?t=resource/res_main&id=mp1443433542
[C_ _curl_]: http://blog.csdn.net/u011127019/article/details/78915704
[curl]: http://blog.csdn.net/u011127019/article/details/78913325
[JS _ .Net]: http://blog.csdn.net/u011127019/article/details/70162104