private static T GetDataCommonMethod<T>(string url, string host, HeaderData headerData) where T : class
{
    //注意Host和请求基网址各个请求可能不同
    var client = new WebClient();
    var headerStr = $"Host: {host}" + "\n" +
                "User-Agent: ......" + "\n" +
                @"Accept: application/json, text/plain, */*" + "\n" +
                "Accept-Encoding: gzip, deflate" + "\n" +
                "Accept-Language: zh-cn" + "\n" +
                $"Cookie: m={headerData.m}; u={headerData.u}; wx={headerData.wx}; ......" + "\n";
    var rawHeaders = headerStr.Split(new[] { '\n', '\r' }, StringSplitOptions.RemoveEmptyEntries).ToList();
    var headerPairs = rawHeaders.Select(x =>
    {
        var items = x.Split(new[] { ':' }, 2, StringSplitOptions.RemoveEmptyEntries);
        var key = items[0].Trim();
        var value = items[1].Trim();
        //ValueTuple是C# 7中的语法，.net framework框架在4.7以上自带
        return new ValueTuple<string, string>(key, value);
     }).ToList();
     headerPairs.ForEach(x =>
     {
         client.Headers.Set(x.Item1, x.Item2);
     });
     //先gzip解压再转string
     byte[] rawBytes = client.DownloadData(url);
     var stream = new MemoryStream(rawBytes);
     GZipStream g = new GZipStream(stream, CompressionMode.Decompress);
     //gzip最后四位是原始长度
     var length = BitConverter.ToInt32(rawBytes, rawBytes.Length - 4);
     byte[] bytes = new byte[length];
     g.Read(bytes, 0, bytes.Length);
     //编码是UTF8
     string s0 = System.Text.Encoding.UTF8.GetString(bytes);

     T result = JsonConvert.DeserializeObject<T>(s0);
     return result;
}

var baseAddress = new Uri("");
var yourText = "";
//UseCookies:处理程序是否使用 CookieContainer 属性来存储服务器Cookie 并在发送请求时使用这些 Cookie
using (var handler = new HttpClientHandler { UseCookies = false })
using (var client = new HttpClient(handler) { BaseAddress = baseAddress })
{
    var formContent = new FormUrlEncodedContent(new[]
    {
        new KeyValuePair<string, string>("id", "1")
    });
    //此处确定请求方式(POST)
    var message = new HttpRequestMessage(HttpMethod.Post, "");
    //添加Cookie信息
    message.Headers.Add("Cookie", yourText);
    message.Content = formContent;
    //使用SendAsync方法，把请求传进去HttpRequestMessage
    var result = await client.SendAsync(message);
    strContent = await result.Content.ReadAsStringAsync();
    var retObj = JsonConvert.DeserializeObject<ResultDto>(strContent);
}