.NET 中發送包含正文數據的 HTTP POST 請求方法詳解

本文介紹在 .NET 中發送 HTTP POST 請求並傳遞正文數據的幾種方法。

1. HttpClient (推薦)

對於 .NET Core 和更新版本的 .NET Framework，HttpClient 是首選的 HTTP 請求方法。它提供異步和高性能操作。

using System.Net.Http;
var client = new HttpClient();
var values = new Dictionary
{
    { "thing1", "hello" },
    { "thing2", "world" }
};
var content = new FormUrlEncodedContent(values);
var response = await client.PostAsync("http://www.example.com/recepticle.aspx", content);

2. 第三方庫

RestSharp:

using RestSharp;
var client = new RestClient("http://example.com");
var request = new RestRequest("resource/{id}");
request.AddParameter("thing1", "Hello");
request.AddParameter("thing2", "world");
var response = client.Post(request);

Flurl.Http:

using Flurl.Http;
var responseString = await "http://www.example.com/recepticle.aspx"
    .PostUrlEncodedAsync(new { thing1 = "hello", thing2 = "world" })
    .ReceiveString();

3. HttpWebRequest (不推薦用於新項目)

POST:

using System.Net;
using System.Text;
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);
using (var stream = request.GetRequestStream()) { stream.Write(data, 0, data.Length); }
var response = request.GetResponse();

GET:

var request = (HttpWebRequest)WebRequest.Create("http://www.example.com/recepticle.aspx");
var response = request.GetResponse();

4. WebClient (不推薦用於新項目)

POST:

using System.Net;
using System.Collections.Specialized;
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);
}

GET:

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

本文比較了多種.NET發送HTTP POST請求的方法，並建議使用HttpClient。 對於新項目，強烈建議使用HttpClient，因為它更現代化，性能更高，並且支持異步操作。