using System;

using System.Collections.Generic;

using System.ComponentModel.DataAnnotations;

using System.Net.Http;

using System.Threading.Tasks;

​

namespace AA04

{

    /// <summary>

    /// HttpClient 送出不同資料作法 2(Multipart/Form Data)

    /// </summary>

    class Program

    {

        static async Task Main(string[] args)

        {

            var result = await LoginAsync(new LoginRequestDto()

            {

                Account = "user1",

                Password = "123"

            });

            Console.WriteLine(result);

        }

        private static async Task<string> LoginAsync(LoginRequestDto loginRequestDto)

        {

            string result = "";

            using (HttpClient client = new HttpClient())

            {

                string endPoint = $"https://localhost:5001/api/PassParameter/FromForm";

                HttpResponseMessage response = null;

​

                #region 使用 MultipartFormDataContent (form-data) 產生要 Post 的資料

                //https://docs.microsoft.com/zh-tw/dotnet/csharp/language-reference/keywords/nameof

                // 準備要 Post 的資料

                Dictionary<string, string> formDataDictionary = new Dictionary<string, string>()

                {

                    {nameof(loginRequestDto.Account), loginRequestDto.Account.ToString() },

                    {nameof(loginRequestDto.Password), loginRequestDto.Password },

                };

​

                #endregion

​

                // https://msdn.microsoft.com/zh-tw/library/system.net.http.multipartformdatacontent(v=vs.110).aspx

                using (var fooContent = new MultipartFormDataContent())

                {

                    foreach (var keyValuePair in formDataDictionary)

                    {

                        fooContent.Add(new StringContent(keyValuePair.Value), keyValuePair.Key);

                    }

                    response = await client.PostAsync(endPoint, fooContent);

                }

​

                result = await response.Content.ReadAsStringAsync();

            }

​

            return result;

        }

    }

​

    #region 呼叫 Web API 會用到的類別

    public class LoginRequestDto

    {

        [Required]

        public string Account { get; set; }

        [Required]

        public string Password { get; set; }

    }

    #endregion

}

​