public class HttpClientHelper
    {
        private static MediaTypeWithQualityHeaderValue JsonMediaType = new MediaTypeWithQualityHeaderValue("application/json");
        public static async Task GetAsync(string url)
        {
            using (var httpClient = new HttpClient())
            {
                var uri = new Uri(url);
                var resp = await httpClient.GetAsync(uri);
                await resp.Content.ReadAsStringAsync();
            }
        }
        public static async Task<T> GetAsync<T>(string url)
        {
            using (var httpClient = new HttpClient())
            {
                var uri = new Uri(url);
                var resp = await httpClient.GetAsync(uri);
                var jsonResult = await resp.Content.ReadAsStringAsync();
                return JsonConvert.DeserializeObject<T>(jsonResult);
            }
        }
        public static async Task PostAsync(string url, object parameters)
        {
            StringContent content = null;
            if (parameters != null)
            {
                var json = JsonConvert.SerializeObject(parameters);
                content = new StringContent(json, Encoding.UTF8);
                content.Headers.ContentType = JsonMediaType;
            }
            using (var httpClient = new HttpClient())
            {
                var uri = new Uri(url);
                var resp = await httpClient.PostAsync(uri, content);
                await resp.Content.ReadAsStringAsync();
            }
        }
        public static async Task<T> PostAsync<T>(string url, object parameters)
        {
            StringContent content = null;
            if (parameters != null)
            {
                var json = JsonConvert.SerializeObject(parameters);
                content = new StringContent(json, Encoding.UTF8);
                content.Headers.ContentType = JsonMediaType;
            }
            using (var httpClient = new HttpClient())
            {
                var uri = new Uri(url);
                var resp = await httpClient.PostAsync(uri, content);
                var jsonResult = await resp.Content.ReadAsStringAsync();
                return JsonConvert.DeserializeObject<T>(jsonResult);
            }
        }
    }