c# post方式请求java form表单api

using System;
using System.Collections.Generic;
using System.Net.Http;

namespace ConsoleApplication1
{
    public class HttpUtil
    {
        public static string test()
        {
            try
            {
                using (var client = new HttpClient())
                {
                    using (var multipartFormDataContent = new MultipartFormDataContent())
                    {
                        var values = new[]
                        {
                            new KeyValuePair<string, string>("to", "tomfang@126.com"),
                            new KeyValuePair<string, string>("from", "tomfang@126.com"),
                            new KeyValuePair<string, string>("subject", "test"),
                            new KeyValuePair<string, string>("bodyText", "test"),
                            new KeyValuePair<string, string>("cc", "tomfang@126.com")
                        };
                        foreach (var keyValuePair in values)
                        {
                            multipartFormDataContent.Add(new StringContent(keyValuePair.Value), String.Format(""{0}"", keyValuePair.Key));
                        }

                        multipartFormDataContent.Add(new ByteArrayContent(System.IO.File.ReadAllBytes(@"D:1.txt")), "attchfile", ""test.jpg"");
                        multipartFormDataContent.Add(new ByteArrayContent(System.IO.File.ReadAllBytes(@"D:2.txt")), "attchfile", ""test.jpg"");
                        multipartFormDataContent.Add(new ByteArrayContent(System.IO.File.ReadAllBytes(@"D:3.txt")), "attchfile", ""test.jpg"");
                        var requestUri = "http://localhost:8081/house/sendEmail";
                        var html = client.PostAsync(requestUri, multipartFormDataContent).Result.Content.ReadAsStringAsync().Result;
                        return html;
                    }
                }
            }
            catch (Exception exx)
            {
                throw exx;
            }
        }
    }
}