钉钉机器人的接口

```csharp
//钉钉机器人响应
        private string DingPush(string txt)
        {
            string url = "https://oapi.dingtalk.com/robot/send?access_token=af861c82c698f0e59123b191979293e5dc3cec9e2a9f01e0a8d7a5da3e87d8fa";
            string data = "{\"text\": {\"content\":\"【提醒】" + txt + "\"},\"msgtype\":\"text\"}";
            try
            {
                System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;   //设置SSL版本
                WebClient client = new WebClient();
                client.Encoding = Encoding.UTF8;    //设置编码
                client.Headers.Add("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.51 Safari/537.36"); //设置请求UA(Chrome)
                client.Headers.Add("Content-Type", "application/json"); //设置为JSON格式
                string reply = client.UploadString(url, data);
                //Console.WriteLine("HTTP POST:" + reply);
                return reply;
            }
            catch (WebException webEx)
            {
                Console.WriteLine("HTTP POST ERROR:" + webEx.ToString());
                return "";
            }
        }