使用HttpClient库的C#程序示例

using System;
using System.Net.Http;
using System.Threading.Tasks;

class Program
{
    static async Task Main()
    {
        await MakeRequest();
    }

    static async Task MakeRequest()
    {
        using (HttpClient client = new HttpClient())
        {
            try
            {
                // 设置要访问的API地址
                string apiUrl = "https://api.example.com";

                // 发送GET请求
                HttpResponseMessage response = await client.GetAsync(apiUrl);

                // 检查响应是否成功
                if (response.IsSuccessStatusCode)
                {
                    // 读取响应内容
                    string responseBody = await response.Content.ReadAsStringAsync();
                    Console.WriteLine("API响应：");
                    Console.WriteLine(responseBody);
                }
                else
                {
                    Console.WriteLine($"请求失败，状态码：{response.StatusCode}");
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine($"发生异常：{ex.Message}");
            }
        }
    }
}

上述示例中使用了HttpClient来发送GET请求，并异步等待响应。