How to save Images to database using ASP.NET Core?

问题:

I am working on a small blog using ASP.NET Core(MVC 6) EF Visual Studio. I have trouble finding how to save images to a database. I have read about IFormfile but I do not really understand how to go about it, I am stuck. I am new to this and would love to have a little help.

I want to save the image to the post I am creating(In the same form). I, therefore, want to save it to postID. Then I need to be able to display the image, how do I do that? I know there is a lot to ask, but I do not know where to turn. Feel free to send links if you have any good tips or ideas.

Thanks in advance!

回答1:

You may find this useful if u need to save to database. This was a modification of https://www.mikesdotnetting.com/article/259/asp-net-mvc-5-with-ef-6-working-with-files and lots of input from k7Boys answer here MVC 6 HttpPostedFileBase?

<input type="file" name="Image" id="Imageinput">

Blog Modal Class should have Img field like;

    public int BlogId{ get; set; }
    ...
    public byte[] Img{ get; set; }

Controller;

    public async Task<IActionResult> Create([Bind("BlogId,...Img")] Blog blog t, IFormFile Image)
    if (ModelState.IsValid)
        {
            if (Image!= null)

            {
                if (Image.Length > 0)

                //Convert Image to byte and save to database

                {

                    byte[] p1 = null;
                    using (var fs1 = Image.OpenReadStream())
                    using (var ms1 = new MemoryStream())
                    {
                        fs1.CopyTo(ms1);
                        p1 = ms1.ToArray();
                    }
                    Blog.Img= p1;

                }
            }

            _context.Add(client);
            await _context.SaveChangesAsync();

            return RedirectToAction("Index");
        }

Took me a couple of hours to get here. Now working on viewing the images in a view, am sure this will not be complex. Enjoy

回答2:

Try this its working fine

controller

[HttpPost]
        [ValidateAntiForgeryToken]
        public async Task<IActionResult> Create([Bind("Id,PostMode,Message,Image,AccountId,Created,Status")] Post post, IFormFile Image)
        {
            if (ModelState.IsValid)
            {
                using (var ms = new MemoryStream())
                {
                    Image.CopyTo(ms);
                    post.Image = ms.ToArray();
                }

                    _context.Add(post);
                await _context.SaveChangesAsync();
                return RedirectToAction(nameof(Index));
            }
            return View(post);
        }

Display Image

@foreach (var item in Model)
        {
    <img class="img-responsive full-width" src="data:image/jpeg;base64,@Convert.ToBase64String(item.Image)" />
}

回答3:

You can use IFormFile to save image posted from view. Below is the sample code.

public class UserProfileViewModel
    {
        public string UserName { get; set; }
        public IFormFile UploadedImage { get; set; }
        public string ImageUrl { get; set; }
    }

In view simply bind it with IFormFile property like:

<img src="@Model.ImageUrl" alt="User Logo" asp-append-version="true" />
<input type="file" asp-for="UploadedImage" />

In your controller you just need to save file on server like:

var filename = ContentDispositionHeaderValue
                                    .Parse(user.UploadedImage.ContentDisposition)
                                    .FileName
                                    .Trim('"');
                    filename = Path.Combine(webRoot, "/Content/UserProfile/", $@"\{filename}");
                    if (Directory.Exists(webRoot + "/Content/UserProfile/"))
                    {
                        using (FileStream fs = System.IO.File.Create(filename))
                        {
                            user.UploadedImage.CopyTo(fs);
                            fs.Flush();
                        }
                    }
model.ImageURL = "~/Content/Brands/" + user.UploadedImage.FileName;