c# - 如何从 Httpclient.SendAsync 调用获取和打印响应

Question

我正在尝试从 HTTP 请求中获取响应，但我似乎做不到。我尝试了以下方法:

public Form1() {     

    HttpClient client = new HttpClient();
    client.BaseAddress = new Uri("someUrl");
    string content = "someJsonString";
    HttpRequestMessage sendRequest = new HttpRequestMessage(HttpMethod.Post, client.BaseAddress);
    sendRequest.Content = new StringContent(content,
                                            Encoding.UTF8,
                                            "application/json");

发送消息:

    ...
    client.SendAsync(sendRequest).ContinueWith(responseTask =>
    {
        Console.WriteLine("Response: {0}", responseTask.Result);
    });
} // end public Form1()

使用这段代码，我得到了状态代码和一些 header 信息，但我没有得到响应本身。我也试过:

  HttpResponseMessage response = await client.SendAsync(sendRequest);

但我被告知要创建一个如下所示的异步方法以使其工作

private async Task<string> send(HttpClient client, HttpRequestMessage msg)
{
    HttpResponseMessage response = await client.SendAsync(msg);
    string rep = await response.Content.ReadAsStringAsync();
}

这是发送“HttpRequest”、获取并打印响应的首选方式吗？我不确定哪种方法是正确的。

Answer 1

这里有一种使用HttpClient的方法，这应该读取请求的响应，以防请求返回状态200，(请求不是BadRequest或者未授权)

string url = 'your url here';

// usually you create on HttpClient per Application (it is the best practice)
HttpClient client = new HttpClient();

using (HttpResponseMessage response = client.GetAsync(url).GetAwaiter().GetResult())
{
    using (HttpContent content = response.Content)
    {
         var json = content.ReadAsStringAsync().GetAwaiter().GetResult();
    }
}

有关完整的详细信息以及如何将 async/await 与 HttpClient 一起使用，您可以阅读 this answer 的详细信息