从 HttpResponseMessage 获取内容/消息

Question

我正在尝试获取 HttpResponseMessage 的内容。 应该是： {"message":"Action '' does not exist,":"success":false} ，但不知道如何从 HttpResponseMessage 中取出来。

HttpClient httpClient = new HttpClient();
HttpResponseMessage response = await httpClient.GetAsync("http://****?action=");
txtBlock.Text = Convert.ToString(response); //wrong!

在这种情况下 txtBlock 将具有价值：

StatusCode: 200, ReasonPhrase: 'OK', Version: 1.1, Content: System.Net.Http.StreamContent, Headers:
{
  Vary: Accept-Encoding
  Keep-Alive: timeout=15, max=100
  Connection: Keep-Alive
  Date: Wed, 10 Apr 2013 20:46:37 GMT
  Server: Apache/2.2.16
  Server: (Debian)
  X-Powered-By: PHP/5.3.3-7+squeeze14
  Content-Length: 55
  Content-Type: text/html
}

Answer 1

我认为最简单的方法就是将最后一行更改为

txtBlock.Text = await response.Content.ReadAsStringAsync(); //right!

这样你就不需要引入任何流阅读器，也不需要任何扩展方法。

Answer 2

您需要调用GetResponse() 。

Stream receiveStream = response.GetResponseStream ();
StreamReader readStream = new StreamReader (receiveStream, Encoding.UTF8);
txtBlock.Text = readStream.ReadToEnd();

Answer 3

试试这个，你可以创建一个这样的扩展方法：

    public static string ContentToString(this HttpContent httpContent)
    {
        var readAsStringAsync = httpContent.ReadAsStringAsync();
        return readAsStringAsync.Result;
    }

然后，简单地调用扩展方法：

txtBlock.Text = response.Content.ContentToString();

我希望这对你有帮助;-)

Answer 4

如果您想将其转换为特定类型（例如在测试中），您可以使用ReadAsAsync扩展方法：

object yourTypeInstance = await response.Content.ReadAsAsync(typeof(YourType));

或以下同步代码：

object yourTypeInstance = response.Content.ReadAsAsync(typeof(YourType)).Result;

更新：还有ReadAsAsync<> 的通用选项，它返回特定类型的实例而不是对象声明的实例：

YourType yourTypeInstance = await response.Content.ReadAsAsync<YourType>();

Answer 5

由 rudivonstaden 的回答

txtBlock.Text = await response.Content.ReadAsStringAsync();

但如果你不想使方法异步，你可以使用

txtBlock.Text = response.Content.ReadAsStringAsync();
txtBlock.Text.Wait();

Wait() 很重要，因为我们正在执行异步操作，我们必须等待任务完成才能继续。

Answer 6

我建议的快速答案是：

response.Result.Content.ReadAsStringAsync().Result

Answer 7

我认为下图对那些需要使用T作为返回类型的人有所帮助。

Answer 8

您可以使用GetStringAsync方法：

var uri = new Uri("http://yoururlhere");
var response = await client.GetStringAsync(uri);

Answer 9

使用块：

using System;
using System.Net;
using System.Net.Http;

This Function will create new HttpClient object, set http-method to GET, set request URL to the function "Url" string argument and apply these parameters to HttpRequestMessage object (which defines settings of SendAsync method). Last line: function sends async GET http request to the specified url, waits for response-message's.Result property(just full response object: headers + body/content), gets.Content property of that full response(body of request, without http headers），将 ReadAsStringAsync() 方法应用于该内容（这也是一些特殊类型的 object），最后，再次等待此异步任务完成 using.Result 属性以获得最终结果字符串，然后返回此字符串作为我们的 function 返回。

static string GetHttpContentAsString(string Url)
    {   
        HttpClient HttpClient = new HttpClient();
        HttpRequestMessage RequestMessage = new HttpRequestMessage(HttpMethod.Get, Url);
        return HttpClient.SendAsync(RequestMessage).Result.Content.ReadAsStringAsync().Result;
    }

较短的版本，它不显示我们的 http 请求的完整“转换”路径，并使用 HttpClient object 的 GetStringAsync 方法。 Function just creates new instance of HttpClient class (an HttpClient object), uses GetStringAsync method to get response body(content) of our http request as an async-task result\promise, and then uses.Result property of that async-task-result得到最终的字符串，然后简单地将这个字符串作为 function 返回。

static string GetStringSync(string Url)
    {
        HttpClient HttpClient = new HttpClient();
        return HttpClient.GetStringAsync(Url).Result;
    }

用法：

const string url1 = "https://microsoft.com";
const string url2 = "https://stackoverflow.com";

ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12; /*sets TLC protocol version explicitly to modern version, otherwise C# could not make http requests to some httpS sites, such as https://microsoft.com*/

Console.WriteLine(GetHttpContentAsString(url1)); /*gets microsoft main page html*/
Console.ReadLine(); /*makes some pause before second request. press enter to make second request*/
Console.WriteLine(GetStringSync(url2)); /*gets stackoverflow main page html*/
Console.ReadLine(); /*press enter to finish*/

完整代码：

Answer 10

截至 2022 年 2 月的更新答案：

var stream = httpResponseMessage.Content.ReadAsStream();
var ms = new MemoryStream();
stream.CopyTo(ms);
var responseBodyBytes = ms.ToArray();