//方法A：HttpClient（首選）
  using System.Net.Http;
       
     private static readonly HttpClient client = new HttpClient();
     //POST
       ar values = new Dictionary<string, string>
    {
        { "thing1", "hello" },
        { "thing2", "world" }
    };

    var content = new FormUrlEncodedContent(values);

    
 
var response = await client.PostAsync("http://www.example.com/recepticle.aspx", content);

        var responseString = await response.Content.ReadAsStringAsync();
        
//GET
var responseString = await client.GetStringAsync("http://www.example.com/recepticle.aspx");

//方法B：第三方庫
//RestSharp
//POST
var client = new
 
 RestClient("http://example.com");
     // client.Authenticator = new HttpBasicAuthenticator(username, password);
     var request = new RestRequest("resource/{id}");
     request.AddParameter("thing1", "Hello");
     request.AddParameter("thing2", "world");
     request.AddHeader("header", "value");
     request.AddFile(
 
"file", path);
     var response = client.Post(request);
     var content = response.Content; // Raw content as string
     var response2 = client.Post<Person>(request);
     var name = response2.Data.Name;
 //Flurl.Http
 using Flurl.Http;
//POST
var responseString = await "http://www.example.com/recepticle.aspx"
    .PostUrlEncodedAsync(new { thing1 = "hello", thing2 = "world" })
    .ReceiveString();
//GET
var responseString = await "http://www.example.com/recepticle.aspx"
    .GetStringAsync();

//方法C：HttpWebRequest
 using System.Net;
    using System.Text;  // For class Encoding
    using System.IO;    // For StreamReader
//POST
var request =         (HttpWebRequest)WebRequest.Create("http://www.example.com/recepticle.aspx");

var postData = "thing1=" + Uri.EscapeDataString("hello");
    postData += "&thing2=" + Uri.EscapeDataString("world");
var data = Encoding.ASCII.GetBytes(postData);

request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = data.Length;

using (var stream = request.GetRequestStream())
{
    stream.Write(data, 0, data.Length);
}

var response = (HttpWebResponse)request.GetResponse();

var responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();
//GET
var request = (HttpWebRequest)WebRequest.Create("http://www.example.com/recepticle.aspx");

var response = (HttpWebResponse)request.GetResponse();

var responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();
//方法D：WebClient
using System.Net;
using System.Collections.Specialized;

//POST
using (var client = new WebClient())
{
    var values = new NameValueCollection();
    values["thing1"] = "hello";
    values["thing2"] = "world";

    var response = client.UploadValues("http://www.example.com/recepticle.aspx", values);

    var responseString = Encoding.Default.GetString(response);
}
//GET
using (var client = new WebClient())
{
    var responseString = client.DownloadString("http://www.example.com/recepticle.aspx");
}