MVC 6 HttpPostedFileBase？

Question

我正在尝试使用 MVC 6 上传图片；但是，我找不到 class HttpPostedFileBase。我检查了 GitHub 并没有任何运气。有谁知道在 MVC6 中上传文件的正确方法？

Answer 1

MVC6中没有HttpPostedFileBase。您可以改用 IFormFile。

示例：https://github.com/aspnet/Mvc/blob/dev/test/WebSites/ModelBindingWebSite/Controllers/FileUploadController.cs

上面的片段link:

public FileDetails UploadSingle(IFormFile file)
{
    FileDetails fileDetails;
    using (var reader = new StreamReader(file.OpenReadStream()))
    {
        var fileContent = reader.ReadToEnd();
        var parsedContentDisposition = ContentDispositionHeaderValue.Parse(file.ContentDisposition);
        fileDetails = new FileDetails
        {
            Filename = parsedContentDisposition.FileName,
            Content = fileContent
        };
    }

    return fileDetails;
}

Answer 2

MVC 6 使用另一种机制来上传文件。如果您想同时上传几个文件，您可以在 GitHub or other sources. Just use IFormFile as a parameter of your action or a collection of files or IFormFileCollection 上获得更多示例：

public async Task<IActionResult> UploadSingle(IFormFile file)
{
    FileDetails fileDetails;
    using (var reader = new StreamReader(file.OpenReadStream()))
    {
        var fileContent = reader.ReadToEnd();
        var parsedContentDisposition = ContentDispositionHeaderValue.Parse(file.ContentDisposition);
        var fileName = parsedContentDisposition.FileName;
    }
    ...
}

[HttpPost]
public async Task<IActionResult> UploadMultiple(ICollection<IFormFile> files)
{
    var uploads = Path.Combine(_environment.WebRootPath,"uploads"); 
    foreach(var file in files)
    {
        if(file.Length > 0)
        {
            var fileName = ContentDispositionHeaderValue.Parse(file.ContentDisposition).FileName.Trim('"');
            await file.SaveAsAsync(Path.Combine(uploads,fileName));
        }
        ...
    }
}

您可以在 asp.net sources. See also ContentDispositionHeaderValue 中查看 IFormFile 的当前合同以获取更多文件信息。

Answer 3

我搜索了很长时间，试图在 .net 核心中将其拼凑起来，结果如下所示。接下来要做的是Base64转换，这样检索和显示会更容易一些。我已经使用 IFormFileCollection 来处理多个文件。

[HttpPost]
    public async Task<IActionResult> Create(IFormFileCollection files)
    {

        Models.File fileIn = new Models.File();
        if(model != null && files != null)
        {
            foreach (var file in files)
            {
                if (file.Length > 0)
                {
                  var fileName = ContentDispositionHeaderValue.Parse(file.ContentDisposition).FileName.Trim('"');

                        byte[] fileBytes = null;
                        using (var fileStream = file.OpenReadStream())
                        using (var ms = new MemoryStream())
                        {
                            fileStream.CopyTo(ms);
                            fileBytes = ms.ToArray();
                            //string s = Convert.ToBase64String(fileBytes);
                            // act on the Base64 data
                        }


                        fileIn.Filename = fileName;
                        fileIn.FileLength = Convert.ToInt32(file.Length);
                        fileIn.FileType = file.ContentType;
                        fileIn.FileTypeId = model.FileTypeId;
                        fileIn.FileData = fileBytes;
                        _context.Add(fileIn);
                        await _context.SaveChangesAsync();
                }
            }
        }
        return View();
    }

编辑

下面是 return 个文件到列表然后下载。

public JsonResult GetAllFiles()
    {

        var files = _context.File
            .Include(a => a.FileCategory)
            .Select(a => new
            {
                id = a.Id.ToString(),
                fileName = a.Filename,
                fileData = a.FileData,
                fileType = a.FileType,
                friendlyName = a.FriendlyName,
                fileCategory = a.FileCategory.Name.ToLower()
            }).ToList();

       return Json(files);
    }

    public FileStreamResult DownloadFileById(int id)
    {
        // Fetching file encoded code from database.
        var file = _context.File.SingleOrDefault(f => f.Id == id);
        var fileData = file.FileData;
        var fileName = file.Filename;

        // Converting to code to byte array
        byte[] bytes = Convert.FromBase64String(fileData);

        // Converting byte array to memory stream.
        MemoryStream stream = new MemoryStream(bytes);

        // Create final file stream result.
        FileStreamResult fileStream = new FileStreamResult(stream, "*/*");

        // File name with file extension.
        fileStream.FileDownloadName = fileName;
        return fileStream;
    }

MVC 6 HttpPostedFileBase？

MVC 6 HttpPostedFileBase?

httppostedfilebase

asp.net-core-mvc