在ASP.NET MVC 6中上传文件 [英] Upload File in ASP.NET MVC 6

问题描述

我在熨烫ASP.NET MVC 6中的文件/图像时遇到了麻烦.大多数教程似乎已经过时，甚至一些新教程似乎都引用了没有意义的东西.

I'm having trouble ironing out the file/image upload in ASP.NET MVC 6. Most tutorials appear to be outdated, and even some of the new ones seem to reference things that don't make sense.

我认为:

<div class="form-group">
    @using (Html.BeginForm("Create", "PostNin", FormMethod.Post, new { enctype = "multipart/form-data" }))
    {
        <label asp-for="NinImageString" class="control-label"></label>
        <input type="file" name="files" class="form-control" />
    }

    @*<input asp-for="NinImageString" class="form-control" />
    <span asp-validation-for="NinImageString" class="text-danger"></span>*@
</div>
<div class="form-group">
    <label asp-for="NinImageCaption" class="control-label"></label>
    <input asp-for="NinImageCaption" class="form-control" />
    <span asp-validation-for="NinImageCaption" class="text-danger"></span>
</div>

然后在我的控制器中:

// GET: PostNins/Create
public IActionResult Create()
{
    return View();
}

[HttpPost]
[ValidateAntiForgeryToken]
public async Task<IActionResult> Create([Bind("Id,NinFk,NinDigit,NinImageString,NinImageCaption,NinNote")] PostNin postNin, IFormFile files)
{
    // need code here
        
    if (ModelState.IsValid)
    {
        _context.Add(postNin);
        await _context.SaveChangesAsync();
        return RedirectToAction(nameof(Index));
    }

    return View(postNin);
}

我的理解是我必须使用 IFormFile 来实现这一目标.

My understanding is that I have to use IFormFile to pull this off.

我想上传带有标题的图像，并将其存储到应用程序文件夹 NinImages 中，以便以后使用.我想我也对此有疑问，但这是另一个问题.

I would like to upload an image with a caption, and store it into the application folder NinImages where I can access it later. I suppose I have questions about that too, but that's for another question.

我的理解是，我必须以某种方式将映像的副本保存到wwwroot下的目录系统中，然后将文件的路径作为字符串保存到数据库中.

My understanding is that I have to somehow save a copy of the image into the directory system, under wwwroot, then save the path of the file as a string to the database.

解决方案:

我的新控制器如下所示.请注意，fileTime只是为每个上载分配一个唯一值，以避免重复.在这种情况下有效，因为一次只能上传一个文件.

My new controller looks like below. As a note, the fileTime is only to assign a unique value to each upload, to avoid duplicates. This works in this case because only one file can be uploaded at a time.

[HttpPost]
    [ValidateAntiForgeryToken]
    public async Task<IActionResult> Create([Bind("Id,NinFk,NinDigit,NinImageString,NinImageCaption,NinNote")] PostNin postNin, IFormFile uploadFile)
    {


        if (uploadFile != null && uploadFile.Length > 0)
        {
            var fileTime = DateTime.UtcNow.ToString("yyMMddHHmmss");
            var fileName = fileTime + Path.GetFileName(uploadFile.FileName);
            var filePath = Path.Combine(Directory.GetCurrentDirectory(), "wwwroot/NinFileUploads", fileName);

            postNin.NinImageString = filePath;
            _context.PostNins.Add(postNin);
            _context.SaveChanges();

            using (var fileStream = new FileStream(filePath, FileMode.Create))
            {
                await uploadFile.CopyToAsync(fileStream);
            }
            //if (ModelState.IsValid)
            //{
            //    _context.Add(postNin);
            //    await _context.SaveChangesAsync();
            //    return RedirectToAction(nameof(Index));
            //}
            return RedirectToAction(nameof(Index));

        }
        return View(postNin);

推荐答案

以下是演示作品:

PostNin类:

public class PostNin
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public string ImagePath { get; set; }
    }

控制器:

public async Task<bool> Create(PostNin postNin,IFormFile upload)
        {     
                if (upload != null && upload.Length > 0)
                {                
                    var fileName = Path.GetFileName(upload.FileName);
                    var filePath = Path.Combine(Directory.GetCurrentDirectory(), "wwwroot/images", fileName);
                    postNin.ImagePath = filePath;
                    _context.PostNins.Add(postNin);
                    _context.SaveChanges();
                    using (var fileSrteam = new FileStream(filePath, FileMode.Create))
                    {
                        await upload.CopyToAsync(fileSrteam);
                    }
                    return true;
                }
                return false;
        }

结果:

这篇关于在ASP.NET MVC 6中上传文件的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！