C# dotNET 5.0 获取外网IP和地理位置

/// <summary>
        /// 获取外网IP和地理位置
        /// </summary>
        /// <returns></returns>
        private static async Task<string> GetWanIpFromPCOnline()
        {
            Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);

            var url = "http://whois.pconline.com.cn/ipJson.jsp";
            var stream = await url.GetAsStreamAsync();
            var streamReader = new StreamReader(stream, Encoding.GetEncoding("GBK"));
            var html = streamReader.ReadToEnd();
            var tmp = html[(html.IndexOf("({") + 2)..].Split(",");
            var ipAddr = tmp[0].Split(":")[1] + "【" + tmp[7].Split(":")[1] + "】";
            return ipAddr.Replace("\"", "");
        }