Web API: Client: HttpClient Message Handlers
原文地址: http://www.asp.net/web-api/overview/web-api-clients/httpclient-message-handlers
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using System; using System.Collections.Generic; using System.Linq; using System.Net.Http; using System.Text; using System.Threading.Tasks; namespace Test.WebAPI.Client { public class CustomClientMessageHandler : DelegatingHandler { private int count = 0; protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) { count++; Console.WriteLine(count); var response = await base.SendAsync(request, cancellationToken); if (!response.IsSuccessStatusCode) { Console.WriteLine("{0}\t{1}\t{2}", request.RequestUri, (int)response.StatusCode, response.Headers.Date); } return response; } } }
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using System; using System.Collections.Generic; using System.Linq; using System.Net.Http; using System.Net.Http.Headers; using System.Text; using System.Threading.Tasks; using Test.EntityFramework.Models; namespace Test.WebAPI.Client { class Program { static void Main(string[] args) { // Custom client message handler TestCustomHanlder().Wait(); Console.WriteLine("Exist..."); Console.ReadLine(); } public static async Task TestCustomHanlder() { using (HttpClient client = HttpClientFactory.Create(new CustomClientMessageHandler())) { client.BaseAddress = new Uri("http://localhost:55165/"); client.DefaultRequestHeaders.Accept.Clear(); client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json")); HttpResponseMessage response = await client.GetAsync("api/test"); // Blocking call // Get if (response.IsSuccessStatusCode) { // Parse the response body. Blocking! var products = await response.Content.ReadAsAsync<IEnumerable<Test.EntityFramework.Models.Test>>(); foreach (var p in products) { Console.WriteLine("{0}\t{1};", p.ID, p.Title); } } else { Console.WriteLine("{0} ({1})", (int)response.StatusCode, response.ReasonPhrase); } } } } }