请使用以下代码进行REST API请求:

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Text;
using System.Json;

namespace ConsoleApplication2
{
    class Program
    {
        private const string URL = "https://XXXX/rest/api/2/component";
        private const string DATA = @"{
            ""name"": ""Component 2"",
            ""description"": ""This is a JIRA component"",
            ""leadUserName"": ""xx"",
            ""assigneeType"": ""PROJECT_LEAD"",
            ""isAssigneeTypeValid"": false,
            ""project"": ""TP""}";

        static void Main(string[] args)
        {
            AddComponent();
        }

        private static void AddComponent()
        {
            System.Net.Http.HttpClient client = new System.Net.Http.HttpClient();
            client.BaseAddress = new System.Uri(URL);
            byte[] cred = UTF8Encoding.UTF8.GetBytes("username:password");
            client.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Basic", Convert.ToBase64String(cred));
            client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));

            System.Net.Http.HttpContent content = new StringContent(DATA, UTF8Encoding.UTF8, "application/json");
            HttpResponseMessage messge = client.PostAsync(URL, content).Result;
            string description = string.Empty;
            if (messge.IsSuccessStatusCode)
            {
                string result = messge.Content.ReadAsStringAsync().Result;
                description = result;
            }
        }
    }
}

在使用。net 4.5或。net Core时调用REST API

我推荐DalSoft。RestClient(注意:是我创建的)。原因是，因为它使用动态类型，您可以在一个流畅的调用中包装所有内容，包括序列化/反序列化。下面是一个工作的PUT示例:

dynamic client = new RestClient("http://jsonplaceholder.typicode.com");

var post = new Post { title = "foo", body = "bar", userId = 10 };

var result = await client.Posts(1).Put(post);

与此无关，我确定，但请使用块包装您的IDisposable对象，以确保适当的处置:

using System;
using System.Net;
using System.IO;

namespace ConsoleProgram
{
    public class Class1
    {
        private const string URL = "https://sub.domain.com/objects.json?api_key=123";
        private const string DATA = @"{""object"":{""name"":""Name""}}";

        static void Main(string[] args)
        {
            Class1.CreateObject();
        }

        private static void CreateObject()
        {
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(URL);
            request.Method = "POST";
            request.ContentType = "application/json";
            request.ContentLength = DATA.Length;
            using (Stream webStream = request.GetRequestStream())
            using (StreamWriter requestWriter = new StreamWriter(webStream, System.Text.Encoding.ASCII))
            {
                requestWriter.Write(DATA);
            }

            try
            {
                WebResponse webResponse = request.GetResponse();
                using (Stream webStream = webResponse.GetResponseStream() ?? Stream.Null)
                using (StreamReader responseReader = new StreamReader(webStream))
                {
                    string response = responseReader.ReadToEnd();
                    Console.Out.WriteLine(response);
                }
            }
            catch (Exception e)
            {
                Console.Out.WriteLine("-----------------");
                Console.Out.WriteLine(e.Message);
            }
        }
    }
}

HTTP GET请求

    string api = this.configuration["getApiUrl"];//Read from Iconfiguration object injected
     public async Task<HttpResponseMessage> GetAsync(string api, ILogger log, params dynamic[] parameters)
            {
                log.LogInformation($"Get Token");
                var token = await GetTokenAsync(this.configuration["ClientId"], this.configuration["AppKey"]).ConfigureAwait(false);
                using (var client = new HttpClient())
                {
                  client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue(BearerTokenName, token);
                    var apiBaseUrl = this.configuration["BaseUrl"];
                   
                    client.BaseAddress = new Uri(apiBaseUrl);
                    var apiUrl = ConstructUrl(api, parameters);
                    var result = await client.GetAsync(apiUrl).ConfigureAwait(false);
    
                    if (result.StatusCode == System.Net.HttpStatusCode.OK)
                    {
                        return result;
                    }
                    else
                    {
                       throw new HttpResponseException(new HttpResponseMessage(result.StatusCode) { Content = new StringContent(result.ReasonPhrase) });
                    }
                }
            }
    

从HttpResponseMessage读取字符串，如下所示

     var client = await this.httpClientService.GetAsync(url, logger, Convert.ToInt32(Id, CultureInfo.InvariantCulture)).ConfigureAwait(false);
     var response = await client.Content.ReadAsStringAsync();

HTTP POST请求

     public async Task<string> PostAsync(string api, string contentValue, ILogger logger)
           {
               var token = await GetTokenAsync(this.configuration["ClientId"], this.configuration["AppKey"]).ConfigureAwait(false);
   
               using (var client = new HttpClient())
               {
                   client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue(BearerTokenName, token);
                   client.BaseAddress = new Uri(resource);
                   var content = new StringContent(contentValue, Encoding.UTF8, MediaTypeNames.Application.Json);
                   var result = await client.PostAsync(new Uri(api, UriKind.Relative), content).ConfigureAwait(false);
   
                   if (result.StatusCode == System.Net.HttpStatusCode.OK)
                   {
                       return await result.Content.ReadAsStringAsync();
                   }
                   else
                   {
                       throw new HttpResponseException(new HttpResponseMessage(result.StatusCode) { Content = new StringContent(result.ReasonPhrase) });
                   }
               }
           }

    var response = await this.httpClientService.PostAsync(this.configuration["getDetails"], content, this.configuration["ApiBaseUrl"], logger).ConfigureAwait(false);
      catch (System.Web.Http.HttpResponseException httpException)
                        {
                            if (httpException.Response.StatusCode == HttpStatusCode.Unauthorized)
                            {
                                logger.LogError($"Failed To Update", httpException);
                            }
                            else
                            {
                                throw;
                            }
                        }
    return response;

GET:

// GET JSON Response
public WeatherResponseModel GET(string url) {
    WeatherResponseModel model = new WeatherResponseModel();
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
    try {
        WebResponse response = request.GetResponse();
        using(Stream responseStream = response.GetResponseStream()) {
            StreamReader reader = new StreamReader(responseStream, Encoding.UTF8);
            model = JsonConvert.DeserializeObject < WeatherResponseModel > (reader.ReadToEnd());
        }
    } catch (WebException ex) {
        WebResponse errorResponse = ex.Response;
        using(Stream responseStream = errorResponse.GetResponseStream()) {
            StreamReader reader = new StreamReader(responseStream, Encoding.GetEncoding("utf-8"));
            String errorText = reader.ReadToEnd();
            // Log errorText
        }
        throw;
    }
    return model;
}

职位:

// POST a JSON string
void POST(string url, string jsonContent) {
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
    request.Method = "POST";

    System.Text.UTF8Encoding encoding = new System.Text.UTF8Encoding();
    Byte[]byteArray = encoding.GetBytes(jsonContent);

    request.ContentLength = byteArray.Length;
    request.ContentType =  @ "application/json";

    using(Stream dataStream = request.GetRequestStream()) {
        dataStream.Write(byteArray, 0, byteArray.Length);
    }

    long length = 0;
    try {
        using(HttpWebResponse response = (HttpWebResponse)request.GetResponse()) {
            // Got response
            length = response.ContentLength;
        }
    } catch (WebException ex) {
        WebResponse errorResponse = ex.Response;
        using(Stream responseStream = errorResponse.GetResponseStream()) {
            StreamReader reader = new StreamReader(responseStream, Encoding.GetEncoding("utf-8"));
            String errorText = reader.ReadToEnd();
            // Log errorText
        }
        throw;
    }
}

注意:为了序列化和反序列化JSON，我使用了Newtonsoft。Json NuGet包。

由于您使用的是Visual Studio 11 Beta，您将希望使用最新的和最好的。新的Web API包含了这方面的类。

参见HttpClient: http://wcf.codeplex.com/wikipage?title=WCF%20HTTP