.NET Core 2.1 HttpClient不返回期望值 [英] .NET Core 2.1 HttpClient doesn't return expected values

问题描述

我正在使用接口从此url调用api http://localhost:55260/api/Accounts/GetList

I am using an interface to call an api from this url http://localhost:55260/api/Accounts/GetList

这是其引用的控制器:

[HttpGet]
[Route("GetList")]
[AllowAnonymous]
public ActionResult<IEnumerable<string>> GetList()
{
    return new string[] { "value1", "value2" };
}

但是，我得到的不是返回字符串，而是:

However, instead of the strings returning, I'm getting this:

这就是我声明httpclient/interface的方式:

This is how I'm declaring my httpclient/interface:

private readonly HttpClient httpClient;
public AuthenticationClient(HttpClient httpClient)
{
    httpClient.BaseAddress = new Uri("http://localhost:55260/api/Accounts");
    httpClient.DefaultRequestHeaders.Accept.Clear();
    httpClient.DefaultRequestHeaders.Accept.Add(
        new MediaTypeWithQualityHeaderValue("application/json"));
    this.httpClient = httpClient;
}

public async Task<IEnumerable<string>> GetDataAsync()
{
    List<string> result = null;
    HttpResponseMessage response = await httpClient.GetAsync("/GetList");
    if (response.IsSuccessStatusCode)
    {
        result = await response.Content.ReadAsAsync<List<string>>();
    }
    return result;
}

我已经在Startup.cs中将其声明为services.AddHttpClient();

I have already declared it in my Startup.cs as services.AddHttpClient();

这就是我所谓的界面

private readonly IAuthenticationClient authenticationClient;
public HomeController(IAuthenticationClient authenticationClient)
{
    this.authenticationClient = authenticationClient;
}

public IActionResult Index()
{
    var result = authenticationClient.GetData();
    return View();
}

我错过了什么吗?或者是否有关于如何使用HttpClients的教程?另外，我该如何通过它发布数据?

Have I missed something or is there a tutorial on how to use HttpClients? Also, how do I post data through this?

推荐答案

您的接口定义了异步调用.换句话说，"GetData"返回的是Task<string>而不是实际值.

your interface defines an async call. in other words "GetData" returns Task<string> not that actual value.

为了获得实际值，请尝试以下操作(徒手编写代码，以便进行调试)

In order to get the actual values try this (coding free hand so not debugged)

public async Task<IActionResult> Index()
{
    var result = await authenticationClient.GetData();
    return View(result);
}

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