C#调用WebApi， 返回的json生成实体的方法

在C#中调用Web API并根据JSON响应生成实体结果，涉及以下几个步骤：

1. 定义实体类

比如我们定义一个User类

1public class User
2{
3    public int Id { get; set; }
4    public string FirstName { get; set; }
5    public string LastName { get; set; }
6    public string Email { get; set; }
7}

2. 发起HTTP请求并解析JSON

接下来，使用HttpClient类来发起HTTP GET请求到Web API，并使用JsonSerializer或第三方库如Newtonsoft.Json来反序列化JSON响应为C#对象。 (基于.NET Core 3.0+ 以上)

1using System;
2using System.Net.Http;
3using System.Text.Json;
4using System.Threading.Tasks;
5
6class Program
7{
8    static async Task Main(string[] args)
9    {
10        using var httpClient = new HttpClient();
11        var response = await httpClient.GetAsync("https://api.example.com/users/1");
12        response.EnsureSuccessStatusCode();
13
14        var json = await response.Content.ReadAsStringAsync();
15        var user = JsonSerializer.Deserialize<User>(json);
16
17        Console.WriteLine($"User: {user.FirstName} {user.LastName}");
18    }
19}

使用Newtonsoft.Json

如果你的项目中使用了Newtonsoft.Json，那么可以这样做：

1using System;
2using System.Net.Http;
3using Newtonsoft.Json;
4using System.Threading.Tasks;
5
6class Program
7{
8    static async Task Main(string[] args)
9    {
10        using var httpClient = new HttpClient();
11        var response = await httpClient.GetAsync("https://api.example.com/users/1");
12        response.EnsureSuccessStatusCode();
13
14        var json = await response.Content.ReadAsStringAsync();
15        var user = JsonConvert.DeserializeObject<User>(json);
16
17        Console.WriteLine($"User: {user.FirstName} {user.LastName}");
18    }
19}