如何以multipart/form-data类型从Asp.net MVC向外部api发送请求

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

public class HomeController : Controller
{
    public async Task<IActionResult> SendRequest()
    {
        using (var httpClient = new HttpClient())
        {
            var formData = new MultipartFormDataContent();

            // 添加文本参数
            formData.Add(new StringContent("value1"), "param1");
            formData.Add(new StringContent("value2"), "param2");

            // 添加文件参数
            var fileContent = new ByteArrayContent(System.IO.File.ReadAllBytes("path/to/file"));
            formData.Add(fileContent, "fileParam", "filename.ext");

            // 发送请求
            var response = await httpClient.PostAsync("https://api.example.com/endpoint", formData);

            // 处理响应
            if (response.IsSuccessStatusCode)
            {
                var result = await response.Content.ReadAsStringAsync();
                // 处理成功响应
            }
            else
            {
                // 处理错误响应
            }
        }

        return View();
    }
}