ASP.Net MVC将.zip文件存储到数据库中作为模型的一部分？

Question

I'm trying to create an application that can store student assignments and allow me to view them and download them from the browser. I would like to be able to upload a .zip file to the model, and have that be stored in the database with the rest of the items in the model. I don't know how to add file uploads or how to to store files to the database. I managed to make my application to only store the id and student name to the database.

Here is how my model looks. I'm not sure what parameter to add here to that it allows my model to hold a .zip file which will be stored in the database, so right now I am storing everything else.

Assignment:

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Web;

namespace ProjectVoting.Models
{
    public class Assignment
    {
        [Key]
        public int Id { get; set; }
        public string StudentName { get; set; }
        public int Votes { get; set; }

    }
}

And here is how my controller looks. It allows all CRUD operations for what I have in the model as of right now.

AssignmentController:

using ProjectVoting.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Web;
using System.Web.Mvc;

namespace ProjectVoting.Controllers
{
    public class AssignmentController : Controller
    {

        ApplicationDbContext context;

        public AssignmentController()
        {
            context = new ApplicationDbContext();
        }

        // GET: Assignment
        public ActionResult Index()
        {
            return View(context.Assignments.ToList());
        }

        // GET: Assignment/Details/5
        public ActionResult Details(int id)
        {
            return View();
        }

        // GET: Assignment/Create
        [HttpGet]
        public ActionResult Create()
        {

            return View();
        }

        // POST: Assignment/Create
        [HttpPost]
        public ActionResult Create(Assignment assignment)
        {

            try
            {
                if (ModelState.IsValid)
                {
                    context.Assignments.Add(assignment);
                    context.SaveChanges();
                    return RedirectToAction("Index");
                }
                return View(assignment);
            }
            catch (Exception e)
            {
                return View();
            }

        }

        // GET: Assignment/Edit/5
        public ActionResult Edit(int? id)
        {
            if (id == null)
                return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
            Assignment assignment = context.Assignments.Find(id);
            if (assignment == null)
                return HttpNotFound();
            return View(assignment);
        }

        // POST: Assignment/Edit/5
        [HttpPost]
        public ActionResult Edit(Assignment assignment)
        {
            try
            {
                if (ModelState.IsValid)
                {
                    context.Entry(assignment).State = System.Data.Entity.EntityState.Modified;
                    context.SaveChanges();
                    return RedirectToAction("Index");
                }

                return View(assignment);
            }
            catch
            {
                return View();
            }
        }

        // GET: Assignment/Delete/5
        public ActionResult Delete(int? id)
        {
            if (id == null)
                return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
            Assignment assignment = context.Assignments.Find(id);
            if (assignment == null)
                return HttpNotFound();
            return View(assignment);
        }

        // POST: Assignment/Delete/5
        [HttpPost]
        public ActionResult Delete(int? id, Assignment ass)
        {
            try
            {
                Assignment assignment = new Assignment();
                if (ModelState.IsValid)
                {
                    if (id == null)
                        return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
                    assignment = context.Assignments.Find(id);
                    if (assignment == null)
                        return HttpNotFound();
                    context.Assignments.Remove(assignment);
                    context.SaveChanges();
                    return RedirectToAction("Index");
                }

                return View(assignment);
            }
            catch
            {
                return View();
            }
        }
    }
}

How can I go changing the code in my model and controller, so that in when I get to my 'Create' view, there is a file upload option with a 'Browse' button form where I can select a .zip file. Then in that page, when I hit submit, it stores the id, name, votes as well as the .zip file into the database. When I view the files in the index, I would like to see the .zip file and have the option to download it.

How can I go about adding this functionality?

Answer 1

If you want to store binary data in DB, you need to add in your model new property

    public byte[] File { get; set; }

You need to modify Create action:

    [HttpPost]
    public ActionResult Create(Assignment assignment,HttpPostedFileBase file)
    {

        try
        {
            if (ModelState.IsValid)
            {
                if (file.ContentLength > 0) {
                     MemoryStream target = new MemoryStream();
                     file.InputStream.CopyTo(target);
                     byte[] data = target.ToArray();
                     assignment.File = data
                }
                context.Assignments.Add(assignment);
                context.SaveChanges();
                return RedirectToAction("Index");
            }
            return View(assignment);
        }
        catch (Exception e)
        {
            return View();
        }

    }

In your "Create" view you need to add enctype="multipart/form-data" to your form and add inside your form

<input type="file" />