//post請求
        public static string PostRequest(string url, HttpContent data)
        {
            var handler = new HttpClientHandler() { UseCookies = false };
            HttpClient client = new HttpClient(handler);
            var message = new HttpRequestMessage(HttpMethod.Post, url);
            message.Content 
 
= data;
            //message.Headers.Authorization = new AuthenticationHeaderValue("Bearer", GetRemoteToken());
            var response = client.SendAsync(message).Result;
            response.EnsureSuccessStatusCode();
            var result = response.Content.ReadAsStringAsync().Result;
            
 
return result;
        }


 //發送文件
        public static void SendFile(string url,string path = @"C:\<filepath>\test.txt")
        {
            using (var client = new HttpClient())
            using (var content = new MultipartFormDataContent())
            {
                client.BaseAddress 
 
= new Uri("http://localhost");

                var fileContent1 = new ByteArrayContent(File.ReadAllBytes(path));
                fileContent1.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
                {
                    FileName = Path.GetFileName(path)
                };
                content.Add(fileContent1);

                var result = client.PostAsync(url, content).Result;
            }
        }

   //httpcontent類型
       //json
            HttpContent content1 = new StringContent("{a:1,b:2}", Encoding.UTF8, "application/json");
       //from
            HttpContent content2 = new FormUrlEncodedContent(new Dictionary<string, string>()
           {
              {"email", "1"},
              {"pwd","11"}
           });

HttpClient封裝方法