如何制作HTTP POST Web请求
如何使用POST方法发出HTTP请求并发送一些数据？ 我可以做GET请求，但不知道如何进行POST 。
有几种方法可以执行HTTP GET和POST请求：
方法A：HttpClient
适用于：.NET Framework 4.5+，.NET Standard 1.1+，.NET Core 1.0+
目前首选的方法。 异步。 通过NuGet可用于其他平台的便携版本。
using System.Net.Http;
建立
建议为您的应用程序的生命周期实例化一个HttpClient并共享它。
private static readonly HttpClient client = new HttpClient();
POST
var 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();
得到
var responseString = await client.GetStringAsync("http://www.example.com/recepticle.aspx");
方法B：第三方库
RestSharp
尝试并测试了与REST API交互的库。 便携。 通过NuGet提供。
Flurl.Http
较新的图书馆运动流畅的API和测试助手。 引擎盖下的HttpClient。 便携。 通过NuGet提供。
using Flurl.Http;
POST
var responseString = await "http://www.example.com/recepticle.aspx"
.PostUrlEncodedAsync(new { thing1 = "hello", thing2 = "world" })
.ReceiveString();
得到
var responseString = await "http://www.example.com/recepticle.aspx"
.GetStringAsync();
方法C：遗留
可用于：.NET Framework 1.1+，.NET Standard 2.0+，.NET Core 1.0+
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=hello";
postData += "&thing2=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();
得到
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（现在也是传统）
可用于：.NET Framework 1.1+，.NET Standard 2.0+，.NET Core 2.0+
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);
}
得到
using (var client = new WebClient())
{
var responseString = client.DownloadString("http://www.example.com/recepticle.aspx");
}
简单的GET请求
using System.Net;
...
using (var wb = new WebClient())
{
var response = wb.DownloadString(url);
}
简单的POST请求
using System.Net;
using System.Collections.Specialized;
...
using (var wb = new WebClient())
{
var data = new NameValueCollection();
data["username"] = "myUser";
data["password"] = "myPassword";
var response = wb.UploadValues(url, "POST", data);
string responseInString = Encoding.UTF8.GetString(response);
}
MSDN有一个示例。
using System;
using System.IO;
using System.Net;
using System.Text;
namespace Examples.System.Net
{
public class WebRequestPostExample
{
public static void Main()
{
// Create a request using a URL that can receive a post.
WebRequest request = WebRequest.Create("http://www.contoso.com/PostAccepter.aspx");
// Set the Method property of the request to POST.
request.Method = "POST";
// Create POST data and convert it to a byte array.
string postData = "This is a test that posts this string to a Web server.";
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
// Set the ContentType property of the WebRequest.
request.ContentType = "application/x-www-form-urlencoded";
// Set the ContentLength property of the WebRequest.
request.ContentLength = byteArray.Length;
// Get the request stream.
Stream dataStream = request.GetRequestStream();
// Write the data to the request stream.
dataStream.Write(byteArray, 0, byteArray.Length);
// Close the Stream object.
dataStream.Close();
// Get the response.
WebResponse response = request.GetResponse();
// Display the status.
Console.WriteLine(((HttpWebResponse)response).StatusDescription);
// Get the stream containing content returned by the server.
dataStream = response.GetResponseStream();
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader(dataStream);
// Read the content.
string responseFromServer = reader.ReadToEnd();
// Display the content.
Console.WriteLine(responseFromServer);
// Clean up the streams.
reader.Close();
dataStream.Close();
response.Close();
}
}
}