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.NET Core-Web API-ファイルのアップロード方法

ファイルアップロードをサポートするための.NET Core Web APIの書き方がわかりません。ファイルのアップロードにASP.NET Core MVCフォームを使用しているのではなく、サーブレット/ JSPコンテナーを使用していることに注意してください。 myproject.jsonの定義方法は次のとおりです。

{
  "dependencies": {
    "Microsoft.NETCore.App": {
      "version": "1.0.1",
      "type": "platform"
    },
    "Microsoft.AspNetCore.Mvc": "1.0.1",
    "Microsoft.AspNetCore.Routing": "1.0.1",
    "Microsoft.AspNetCore.Server.IISIntegration": "1.0.0",
    "Microsoft.AspNetCore.Server.Kestrel": "1.0.1",
    "Microsoft.Extensions.Configuration.EnvironmentVariables": "1.0.0",
    "Microsoft.Extensions.Configuration.FileExtensions": "1.0.0",
    "Microsoft.Extensions.Configuration.Json": "1.0.0",
    "Microsoft.Extensions.Logging": "1.0.0",
    "Microsoft.Extensions.Logging.Console": "1.0.0",
    "Microsoft.Extensions.Logging.Debug": "1.0.0",
    "Microsoft.Extensions.Options.ConfigurationExtensions": "1.0.0",
    "Npgsql": "3.1.9",
    "CoreCompat.Newtonsoft.Json": "9.0.2-beta001",
    "Newtonsoft.Json": "9.0.1"
  },

  "tools": {
    "Microsoft.AspNetCore.Server.IISIntegration.Tools": "1.0.0-preview2-final"
  },

  "frameworks": {
    "netcoreapp1.0": {
      "imports": [
        "dotnet5.6",
        "portable-net45+win8"
      ]
    }
  },

  "buildOptions": {
    "emitEntryPoint": true,
    "preserveCompilationContext": true
  },

  "runtimeOptions": {
    "configProperties": {
      "System.GC.Server": true
    }
  },

  "publishOptions": {
    "include": [
      "wwwroot",
      "**/*.cshtml",
      "appsettings.json",
      "web.config"
    ]
  },

  "scripts": {
    "postpublish": [ "dotnet publish-iis --publish-folder %publish:OutputPath% --framework %publish:FullTargetFramework%" ]
  }
}

MyStartupの定義方法は次のとおりです。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;

using QCService.Models;

namespace QCService
{
    public class Startup
    {
        public Startup(IHostingEnvironment env)
        {
            var builder = new ConfigurationBuilder()
                .SetBasePath(env.ContentRootPath)
                .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
                .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true)
                .AddEnvironmentVariables();
            Configuration = builder.Build();
        }

        public IConfigurationRoot Configuration { get; }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            // Add framework services.
            services.AddMvc();

            //Add SurveysRepository for Dependency Injection
            services.AddSingleton<ISurveysRepository, SurveysRepository>();
            //Add FeedbacksRepository for Dependency Injection
            services.AddSingleton<IFeedbacksRepository, FeedbacksRepository>();
            //Add AttachmentsRepository for Dependency Injection
            services.AddSingleton<IAttachmentsRepository, AttachmentsRepository>();
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
        {
            loggerFactory.AddConsole(Configuration.GetSection("Logging"));
            loggerFactory.AddDebug();

            app.UseMvc();
        }
    }
}

最後に、myControllerの定義方法を示します。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
//Including model classes for Attachments
using QCService.Models;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Hosting;
using System.IO;
using Microsoft.Net.Http.Headers;

// For more information on enabling Web API for empty projects, visit http://go.Microsoft.com/fwlink/?LinkID=397860

namespace QCService.Controllers
{
    [Route("api/[controller]")]
    public class AttachmentsController : Controller
    {
        public IAttachmentsRepository AttachmentItems { get; set; }
        public AttachmentsController(IAttachmentsRepository attachmentItems)
        {
            AttachmentItems = attachmentItems;
        }

        // GET: api/Attachments
        [HttpGet] /*http://localhost:52770/api/Attachments*/
        public IEnumerable<Attachments> Get()
        {
            return AttachmentItems.GetAllAttachments();
        }

        // GET api/Attachments/5
        [HttpGet("{id}")] /*http://localhost:52770/api/Attachments/{AttachmentID}*/
        public Attachments Get(int id)
        {
            return AttachmentItems.GetAttachment(id);
        }

        // GET api/Attachments/5
        [HttpGet("Feedback/{id}")] /*http://localhost:52770/api/Attachments/Feedback/{FeedbackID}*/
        public IEnumerable<Attachments> GetFeedbackAttachments(int id)
        {
            return AttachmentItems.GetFeedbackAttachments(id);
        }

        // POST api/Attachments
        [HttpPost]/*http://localhost:52770/api/Attachments/*/
        public async Task<IActionResult> PostFiles(ICollection<IFormFile> files)
        {
            try
            {
                System.Console.WriteLine("You received the call!");
                WriteLog("PostFiles call received!", true);
                //We would always copy the attachments to the folder specified above but for now dump it wherver....
                long size = files.Sum(f => f.Length);

                // full path to file in temp location
                var filePath = Path.GetTempFileName();
                var fileName = Path.GetTempFileName();

                foreach (var formFile in files)
                {
                    if (formFile.Length > 0)
                    {
                        using (var stream = new FileStream(filePath, FileMode.Create))
                        {
                            await formFile.CopyToAsync(stream);
                            //formFile.CopyToAsync(stream);
                        }
                    }
                }

                // process uploaded files
                // Don't rely on or trust the FileName property without validation.
                //Displaying File Name for verification purposes for now -Rohit

                return Ok(new { count = files.Count, fileName, size, filePath });
            }
            catch (Exception exp)
            {
                System.Console.WriteLine("Exception generated when uploading file - " + exp.Message);
                WriteLog("Exception generated when uploading file - " + exp.Message, true);
                string message = $"file / upload failed!";
                return Json(message);
            }
        }

        /// <summary>
        /// Writes a log entry to the local file system
        /// </summary>
        /// <param name="Message">Message to be written to the log file</param>
        /// <param name="InsertNewLine">Inserts a new line</param>
        public void WriteLog(string Message, bool InsertNewLine)
        {
            LogActivity ologObject = null;
            try
            {
                string MessageString = (InsertNewLine == true ? Environment.NewLine : "") + Message;
                if (ologObject == null)
                    ologObject = LogActivity.GetLogObject();
                ologObject.WriteLog(Message, InsertNewLine);
            }
            catch (Exception ex)
            {
                Console.WriteLine("Unable to write to the log file : " + ex.Message);
                Console.WriteLine("Stack Trace : " + ex.StackTrace);
            }
        }
    }
}

https://docs.Microsoft.com/en-us/aspnet/core/mvc/models/file-uploads でこのリンクを確認しましたが、機能しません。どんな助けも大歓迎です!!!

GoogleのAdvanced Rest Clientを使用して、次のようにデータを投稿します。 これがPOSTリクエスト

次のメッセージで応答が失敗し続けます...ステータス：500：内部サーバーエラーロード時間：62 ms応答ヘッダー5要求ヘッダー2リダイレクト0タイミングContent-Type：multipart/form-data; boundary = ---- WebKitFormBoundary0RKUhduCjSNZOEMN Content-Length：9106ソースメッセージ

POST/api/Attachments HTTP/1.1ホスト：localhost：52770 content-type：multipart/form-data; boundary = ---- WebKitFormBoundary0RKUhduCjSNZOEMN content-length：9106

------ WebKitFormBoundary0RKUhduCjSNZOEMN Content-Disposition：form-data; name = "fileUpload1"; filename = "1i4ymeoyov_In_the_Wild_Testing.png" Content-Type：image/png

�PNG

IHDR、I�3（tEXtSoftwareAdobeImageReadyq�e<iTXtXML：com.Adobe.xmp�8^2IDATx��]pU����@a�H�Pe�P8��Ȉ��b�̌3�p�q �*�7''���Yf��O�atD��（<�h¦DLXdOH������=}���}ov8_U�..... ------ WebKitFormBoundary0RKUhduCjSNZOEMN- -

c#asp.net-corefile-uploadservlet-3.0
11
Rohit

これが根本的な原因です：form-data; name = "fileUpload1"

名前「fileUpload1」は、アクションPostFiles（ICollection <IFormFile> files）の宣言と一致する「files」である必要があります

8
Bodom Vu

あなたの問題はchrome 56。

ARCは新しいChromeバージョン：56.0.2924.76 でファイルを送信できません

この問題は、郵便配達員とChromeRestClientの両方に影響します

簡単な回避策は、Use XHRオプションを有効にし、ヘッダーContent-Type：multipart/form-dataを削除することです。

これは郵便配達員とクロームの両方で機能します

0
Khalil

こんにちはcontentypeの「multipart/form-data」を「application/octet-stream」に変更します。エラーなしでコードブロック内に移動できます。次のようなコードを試して、ファイルをバイナリタイプとして送信してください

`  byte[] fileToSend = File.ReadAllBytes(filePath);
                HttpWebRequest httpWebRequest = (HttpWebRequest)WebReq
uest.Create(url);
                httpWebRequest.Method = "POST";
                httpWebRequest.ContentType = "application/octet-stream";
                httpWebRequest.ContentLength = fileToSend.Length;              

                using (Stream requestStream = httpWebRequest.GetRequestStream())
                {
                    requestStream.Write(fileToSend, 0, fileToSend.Length);
                    requestStream.Close();
                }`

うまくいきます..ありがとう

0
madan

request で、URLが正しくありません。コントローラー上のルートを確認します。[Route（ "api/[controller]"）]で、アクションメソッド名はPostFiles。したがって、正しいURLは http：// localhost：52770/api/Attachments/PostFiles になります

URLを修正するか、アクションメソッドの名前をIndexに変更します

0
Pradeep Kumar