Blazor użycie Web API

_Imports.razor

@layout MainLayout
@using ApiDemo.Shared
@using ApiDemo.Client.Services

FetchData.razor

@page "/fetchdata"
@inject IWeatherForecastService Service

<h1>Weather forecast</h1>

<p>This component demonstrates fetching data from the server.</p>

@if (forecasts == null)
{
    <p><em>Loading...</em></p>
}
else
{
    <table class="table">
        <thead>
            <tr>
                <th>Date</th>
                <th>Temp. (C)</th>
                <th>Temp. (F)</th>
                <th>Summary</th>
            </tr>
        </thead>
        <tbody>
            @foreach (var forecast in forecasts)
            {
                <tr>
                    <td>@forecast.Date.ToShortDateString()</td>
                    <td>@forecast.TemperatureC</td>
                    <td>@forecast.TemperatureF</td>
                    <td>@forecast.Summary</td>
                </tr>
            }
        </tbody>
    </table>
}

@functions {
    WeatherForecast[] forecasts;

    protected override async Task OnInitAsync()
    {
        forecasts = await Service.GetAsync();
    }
}

SampleDataController.cs

[Route("api/[controller]")]
public class SampleDataController : Controller
{
    private static string[] Summaries = new[]
    {
        "Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
    };

    [HttpGet("[action]")]
    public IEnumerable<WeatherForecast> WeatherForecasts()
    {
        var rng = new Random();
        return Enumerable.Range(1, 5).Select(index => new WeatherForecast
        {
            Date = DateTime.Now.AddDays(index),
            TemperatureC = rng.Next(-20, 55),
            Summary = Summaries[rng.Next(Summaries.Length)]
        });
    }
}

Startup.cs

public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddScoped<IWeatherForecastService, WeatherForecastService>();
    }

    public void Configure(IComponentsApplicationBuilder app)
    {
        app.AddComponent<App>("app");
    }
}

WeatherForecast.cs

public class WeatherForecast
{
    public DateTime Date { get; set; }

    public int TemperatureC { get; set; }

    public string Summary { get; set; }

    public int TemperatureF => 32 + (int)(TemperatureC / 0.5556);
}

WeatherForecastService.cs

public class WeatherForecastService : IWeatherForecastService
{
    private readonly HttpClient _client;

    public WeatherForecastService(HttpClient client)
    {
        _client = client;
    }

    public async Task<WeatherForecast[]> GetAsync()
    {
        return await _client.GetJsonAsync<WeatherForecast[]>("api/SampleData/WeatherForecasts");
    }
}

public interface IWeatherForecastService
{
    Task<WeatherForecast[]> GetAsync();
}