我如何能使一个HTTP POST请求和发送数据的主体?
当前回答
这是一个完整的JSON格式发送/接收数据的工作示例,我使用Visual Studio 2013 Express Edition:
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.OleDb;
using System.IO;
using System.Linq;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;
using System.Web.Script.Serialization;
namespace ConsoleApplication1
{
class Customer
{
public string Name { get; set; }
public string Address { get; set; }
public string Phone { get; set; }
}
public class Program
{
private static readonly HttpClient _Client = new HttpClient();
private static JavaScriptSerializer _Serializer = new JavaScriptSerializer();
static void Main(string[] args)
{
Run().Wait();
}
static async Task Run()
{
string url = "http://www.example.com/api/Customer";
Customer cust = new Customer() { Name = "Example Customer", Address = "Some example address", Phone = "Some phone number" };
var json = _Serializer.Serialize(cust);
var response = await Request(HttpMethod.Post, url, json, new Dictionary<string, string>());
string responseText = await response.Content.ReadAsStringAsync();
List<YourCustomClassModel> serializedResult = _Serializer.Deserialize<List<YourCustomClassModel>>(responseText);
Console.WriteLine(responseText);
Console.ReadLine();
}
/// <summary>
/// Makes an async HTTP Request
/// </summary>
/// <param name="pMethod">Those methods you know: GET, POST, HEAD, etc...</param>
/// <param name="pUrl">Very predictable...</param>
/// <param name="pJsonContent">String data to POST on the server</param>
/// <param name="pHeaders">If you use some kind of Authorization you should use this</param>
/// <returns></returns>
static async Task<HttpResponseMessage> Request(HttpMethod pMethod, string pUrl, string pJsonContent, Dictionary<string, string> pHeaders)
{
var httpRequestMessage = new HttpRequestMessage();
httpRequestMessage.Method = pMethod;
httpRequestMessage.RequestUri = new Uri(pUrl);
foreach (var head in pHeaders)
{
httpRequestMessage.Headers.Add(head.Key, head.Value);
}
switch (pMethod.Method)
{
case "POST":
HttpContent httpContent = new StringContent(pJsonContent, Encoding.UTF8, "application/json");
httpRequestMessage.Content = httpContent;
break;
}
return await _Client.SendAsync(httpRequestMessage);
}
}
}
其他回答
当使用Windows.Web.Http命名空间时,对于POST而不是FormUrlEncodedContent,我们编写HttpFormUrlEncodedContent。同样,响应类型为HttpResponseMessage。其余的就像Evan Mulawski写的那样。
如果你喜欢一个流畅的API,你可以使用Tiny.RestClient。在NuGet上可以买到。
var client = new TinyRestClient(new HttpClient(), "http://MyAPI.com/api");
// POST
var city = new City() { Name = "Paris", Country = "France" };
// With content
var response = await client.PostRequest("City", city)
.ExecuteAsync<bool>();
为什么这不是完全无关紧要的?执行请求并不是处理结果。而且似乎还涉及到一些。net Bug——参见HttpClient中的Bug。GetAsync应该抛出WebException,而不是TaskCanceledException
我最终得到了这样的代码:
static async Task<(bool Success, WebExceptionStatus WebExceptionStatus, HttpStatusCode? HttpStatusCode, string ResponseAsString)> HttpRequestAsync(HttpClient httpClient, string url, string postBuffer = null, CancellationTokenSource cts = null) {
try {
HttpResponseMessage resp = null;
if (postBuffer is null) {
resp = cts is null ? await httpClient.GetAsync(url) : await httpClient.GetAsync(url, cts.Token);
} else {
using (var httpContent = new StringContent(postBuffer)) {
resp = cts is null ? await httpClient.PostAsync(url, httpContent) : await httpClient.PostAsync(url, httpContent, cts.Token);
}
}
var respString = await resp.Content.ReadAsStringAsync();
return (resp.IsSuccessStatusCode, WebExceptionStatus.Success, resp.StatusCode, respString);
} catch (WebException ex) {
WebExceptionStatus status = ex.Status;
if (status == WebExceptionStatus.ProtocolError) {
// Get HttpWebResponse so that you can check the HTTP status code.
using (HttpWebResponse httpResponse = (HttpWebResponse)ex.Response) {
return (false, status, httpResponse.StatusCode, httpResponse.StatusDescription);
}
} else {
return (false, status, null, ex.ToString());
}
// https://devblogs.microsoft.com/dotnet/net-5-new-networking-improvements/
} catch (TaskCanceledException ex) when (ex.InnerException is TimeoutException) {
return (false, ex.ToString(), null, WebExceptionStatus.Timeout);
} catch (TaskCanceledException ex) {
return (false, ex.ToString(), null, WebExceptionStatus.RequestCanceled);
} catch (Exception ex) {
return (false, WebExceptionStatus.UnknownError, null, ex.ToString());
}
}
这将根据postBuffer是否为空来执行GET或POST操作。
如果Success为true,响应将在ResponseAsString中。
如果Success为false,你可以检查WebExceptionStatus, HttpStatusCode和ResponseAsString,看看哪里出了问题。
在. net Core中,你可以用下面的代码进行POST调用。在这里,我为这段代码添加了一些额外的特性,这样您就可以让您的代码在代理后工作,如果有网络凭据的话。
在这里我还提到,您可以更改消息的编码。
HttpClient client = GetHttpClient(_config);
if (headers != null)
{
foreach (var header in headers)
{
client.DefaultRequestHeaders.TryAddWithoutValidation(header.Key, header.Value);
}
}
client.BaseAddress = new Uri(baseAddress);
Encoding encoding = Encoding.UTF8;
var result = await client.PostAsync(url, new StringContent(body, encoding, "application/json")).ConfigureAwait(false);
if (result.IsSuccessStatusCode)
{
return new RequestResponse { severity = "Success", httpResponse = result.Content.ReadAsStringAsync().Result, StatusCode = result.StatusCode };
}
else
{
return new RequestResponse { severity = "failure", httpResponse = result.Content.ReadAsStringAsync().Result, StatusCode = result.StatusCode };
}
public HttpClient GetHttpClient(IConfiguration _config)
{
bool ProxyEnable = Convert.ToBoolean(_config["GlobalSettings:ProxyEnable"]);
HttpClient client = null;
if (!ProxyEnable)
{
client = new HttpClient();
}
else
{
string ProxyURL = _config["GlobalSettings:ProxyURL"];
string ProxyUserName = _config["GlobalSettings:ProxyUserName"];
string ProxyPassword = _config["GlobalSettings:ProxyPassword"];
string[] ExceptionURL = _config["GlobalSettings:ExceptionURL"].Split(';');
bool BypassProxyOnLocal = Convert.ToBoolean(_config["GlobalSettings:BypassProxyOnLocal"]);
bool UseDefaultCredentials = Convert.ToBoolean(_config["GlobalSettings:UseDefaultCredentials"]);
WebProxy proxy = new WebProxy
{
Address = new Uri(ProxyURL),
BypassProxyOnLocal = BypassProxyOnLocal,
UseDefaultCredentials = UseDefaultCredentials,
BypassList = ExceptionURL,
Credentials = new NetworkCredential(ProxyUserName, ProxyPassword)
};
HttpClientHandler handler = new HttpClientHandler { Proxy = proxy };
client = new HttpClient(handler, true);
}
return client;
}
如果需要POST JSON消息体,可以使用以下方法。假设您有一个名为m的类实例。
string jsonMessage = JsonConvert.SerializeObject(m);
// Make POST call
using (HttpClient client = new HttpClient())
{
HttpRequestMessage requestMessage = new
HttpRequestMessage(HttpMethod.Post, "<url here>");
requestMessage.Content = new StringContent(jsonMessage, Encoding.UTF8, "application/json");
HttpResponseMessage response = client.SendAsync(requestMessage).Result;
if (response.StatusCode == System.Net.HttpStatusCode.OK)
{
// Do something here
}
}
推荐文章
- 实体框架核心:在上一个操作完成之前,在此上下文中开始的第二个操作
- 如何为构造函数定制Visual Studio的私有字段生成快捷方式?
- 为什么Visual Studio 2015/2017/2019测试运行器没有发现我的xUnit v2测试
- 如何使用JSON确保字符串是有效的JSON。网
- AppSettings从.config文件中获取值
- 通过HttpClient向REST API发布一个空体
- 如何检查IEnumerable是否为空或空?
- 自动化invokerrequired代码模式
- 没有ListBox。SelectionMode="None",是否有其他方法禁用列表框中的选择?
- 在c#代码中设置WPF文本框的背景颜色
- 在c#中,什么是单子?
- c#和Java中的泛型有什么不同?和模板在c++ ?
- c#线程安全快速(est)计数器
- 如何将此foreach代码转换为Parallel.ForEach?
- 如何在iis7应用程序池中设置。net Framework 4.5版本