如何使用C#在POST请求中发送json请求体数据

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

class Program
{
    static async Task Main(string[] args)
    {
        string url = "http://example.com/api/endpoint"; // 设置请求的URL地址

        // 创建HttpClient实例
        using (HttpClient client = new HttpClient())
        {
            // 设置请求头，指定请求体的内容类型为application/json
            client.DefaultRequestHeaders.Add("Accept", "application/json");
            client.DefaultRequestHeaders.Add("User-Agent", "Your User Agent");

            // 构造请求体数据
            string jsonData = "{\"key1\":\"value1\",\"key2\":\"value2\"}";

            // 将请求体数据转换为StringContent对象
            StringContent content = new StringContent(jsonData, Encoding.UTF8, "application/json");

            // 发送POST请求，并获取响应
            HttpResponseMessage response = await client.PostAsync(url, content);

            // 检查响应是否成功
            if (response.IsSuccessStatusCode)
            {
                // 处理成功响应
                string responseContent = await response.Content.ReadAsStringAsync();
                Console.WriteLine(responseContent);
            }
            else
            {
                // 处理错误响应
                Console.WriteLine("Error: " + response.StatusCode);
            }
        }
    }
}