我的方法和上面差不多，我将向您展示我的代码以及如何使用MYSSQL数据库。。。

数据库中的文档表-

int Id（PK），字符串Url，字符串描述，创建者，租户ID上传日期

上面的代码ID是主键，URL是文件的名称（末尾有文件类型），要在文档视图中输出的文件描述，CreatedBy是上载文件的人，tenncyId，dateUploaded

在视图中，必须定义enctype，否则它将无法正常工作。

@using (Html.BeginForm("Upload", "Document", FormMethod.Post, new { enctype = "multipart/form-data" }))
{
<div class="input-group">
    <label for="file">Upload a document:</label>
    <input type="file" name="file" id="file" />
</div>
}

上面的代码将给你一个浏览按钮，然后在我的项目中，我有一个基本上名为IsValidImage的类，它只是检查文件大小是否在指定的最大大小之下，检查它是否是IMG文件，这都在类bool函数中。所以，如果true返回true。

public static bool IsValidImage(HttpPostedFileBase file, double maxFileSize, ModelState ms )
{
    // make sur the file isnt null.
    if( file == null )
        return false;

// the param I normally set maxFileSize is 10MB  10 * 1024 * 1024 = 10485760 bytes converted is 10mb
var max = maxFileSize * 1024 * 1024;

// check if the filesize is above our defined MAX size.
if( file.ContentLength > max )
    return false;

try
{
    // define our allowed image formats
    var allowedFormats = new[] { ImageFormat.Jpeg, ImageFormat.Png, ImageFormat.Gif, ImageFormat.Bmp };

    // Creates an Image from the specified data stream.      
    using (var img = Image.FromStream(file.InputStream))
    {
        // Return true if the image format is allowed
        return allowedFormats.Contains(img.RawFormat);
    }
}
catch( Exception ex )
{
    ms.AddModelError( "", ex.Message );                 
}
return false;   
}

因此，在控制器中：

if (!Code.Picture.IsValidUpload(model.File, 10, true))
{                
    return View(model);
}

// Set the file name up... Being random guid, and then todays time in ticks. Then add the file extension
// to the end of the file name
var dbPath = Guid.NewGuid().ToString() + DateTime.UtcNow.Ticks + Path.GetExtension(model.File.FileName);

// Combine the two paths together being the location on the server to store it
// then the actual file name and extension.
var path = Path.Combine(Server.MapPath("~/Uploads/Documents/"), dbPath);

// set variable as Parent directory I do this to make sure the path exists if not
// I will create the directory.
var directoryInfo = new FileInfo(path).Directory;

if (directoryInfo != null)
    directoryInfo.Create();

// save the document in the combined path.
model.File.SaveAs(path);

// then add the data to the database
_db.Documents.Add(new Document
{
    TenancyId = model.SelectedTenancy,
    FileUrl = dbPath,
    FileDescription = model.Description,
    CreatedBy = loggedInAs,
    CreatedDate = DateTime.UtcNow,
    UpdatedDate = null,
    CanTenantView = true
});

_db.SaveChanges();
model.Successfull = true;

如果你碰巧像我一样在这里跌跌撞撞，想知道尽管代码正确，为什么你的代码仍然不工作。然后，请在输入控件中查找name属性，您可能会意外错过或从未将其放在首位。

<input class="custom-file-input" name="UploadFile" id="UploadFile" type="file" onchange="ValidateFile(this);" accept=".xls, .xlsx">
                             

保存多个文件的简单方法

cshtml

@using (Html.BeginForm("Index","Home",FormMethod.Post,new { enctype = "multipart/form-data" }))
{
    <label for="file">Upload Files:</label>
    <input type="file" multiple name="files" id="files" /><br><br>
    <input type="submit" value="Upload Files" />
    <br><br>
    @ViewBag.Message
}

控制器

[HttpPost]
        public ActionResult Index(HttpPostedFileBase[] files)
        {
            foreach (HttpPostedFileBase file in files)
            {
                if (file != null && file.ContentLength > 0)
                    try
                    {
                        string path = Path.Combine(Server.MapPath("~/Files"), Path.GetFileName(file.FileName));
                        file.SaveAs(path);
                        ViewBag.Message = "File uploaded successfully";
                    }
                    catch (Exception ex)
                    {
                        ViewBag.Message = "ERROR:" + ex.Message.ToString();
                    }

                else
                {
                    ViewBag.Message = "You have not specified a file.";
                }
            }
            return View();
        }

由于我在IE浏览器中发现了上传文件的问题，我建议这样处理。

View

@using (Html.BeginForm("UploadFile", "Home", FormMethod.Post, new { enctype = "multipart/form-data" }))
{
    <input type="file" name="file" />
    <input type="submit" value="Submit" />
}

控制器

public class HomeController : Controller
{
    public ActionResult UploadFile()
    {
        return View();
    }

    [HttpPost]
    public ActionResult UploadFile(MyModal Modal)
    {
            string DocumentName = string.Empty;
            string Description = string.Empty;

            if (!String.IsNullOrEmpty(Request.Form["DocumentName"].ToString()))
                DocumentName = Request.Form["DocumentName"].ToString();
            if (!String.IsNullOrEmpty(Request.Form["Description"].ToString()))
                Description = Request.Form["Description"].ToString();

            if (!String.IsNullOrEmpty(Request.Form["FileName"].ToString()))
                UploadedDocument = Request.Form["FileName"].ToString();

            HttpFileCollectionBase files = Request.Files;

            string filePath = Server.MapPath("~/Root/Documents/");
            if (!(Directory.Exists(filePath)))
                Directory.CreateDirectory(filePath);
            for (int i = 0; i < files.Count; i++)
            {
                HttpPostedFileBase file = files[i];
                // Checking for Internet Explorer  
                if (Request.Browser.Browser.ToUpper() == "IE" || Request.Browser.Browser.ToUpper() == "INTERNETEXPLORER")
                {
                    string[] testfiles = file.FileName.Split(new char[] { '\\' });
                    fname = testfiles[testfiles.Length - 1];
                    UploadedDocument = fname;
                }
                else
                {
                    fname = file.FileName;
                    UploadedDocument = file.FileName;
                }
                file.SaveAs(fname);
                return RedirectToAction("List", "Home");
}

您不使用文件输入控件。ASP.NET MVC中未使用服务器端控件。查看下面的博客文章，其中说明了如何在ASP.NET MVC中实现这一点。

因此，您将首先创建一个HTML表单，其中包含文件输入：

@using (Html.BeginForm("Index", "Home", FormMethod.Post, new { enctype = "multipart/form-data" }))
{
    <input type="file" name="file" />
    <input type="submit" value="OK" />
}

然后你会有一个控制器来处理上传：

public class HomeController : Controller
{
    // This action renders the form
    public ActionResult Index()
    {
        return View();
    }

    // This action handles the form POST and the upload
    [HttpPost]
    public ActionResult Index(HttpPostedFileBase file)
    {
        // Verify that the user selected a file
        if (file != null && file.ContentLength > 0) 
        {
            // extract only the filename
            var fileName = Path.GetFileName(file.FileName);
            // store the file inside ~/App_Data/uploads folder
            var path = Path.Combine(Server.MapPath("~/App_Data/uploads"), fileName);
            file.SaveAs(path);
        }
        // redirect back to the index action to show the form once again
        return RedirectToAction("Index");        
    }
}

我给你简单易懂的方法。

首先，必须在.Cshtml文件中编写以下代码。

<input name="Image" type="file" class="form-control" id="resume" />

然后在控制器中输入以下代码：

if (i > 0) {
    HttpPostedFileBase file = Request.Files["Image"];


    if (file != null && file.ContentLength > 0) {
        if (!string.IsNullOrEmpty(file.FileName)) {
            string extension = Path.GetExtension(file.FileName);

            switch ((extension.ToLower())) {
                case ".doc":
                    break;
                case ".docx":
                    break;
                case ".pdf":
                    break;
                default:
                    ViewBag.result = "Please attach file with extension .doc , .docx , .pdf";
                    return View();
            }

            if (!Directory.Exists(Server.MapPath("~") + "\\Resume\\")) {
                System.IO.Directory.CreateDirectory(Server.MapPath("~") + "\\Resume\\");
            }

            string documentpath = Server.MapPath("~") + "\\Resume\\" + i + "_" + file.FileName;
            file.SaveAs(documentpath);
            string filename = i + "_" + file.FileName;
            result = _objbalResume.UpdateResume(filename, i);
            Attachment at = new Attachment(documentpath);

            //ViewBag.result = (ans == true ? "Thanks for contacting us.We will reply as soon as possible" : "There is some problem. Please try again later.");
        }
    } else {
        ...
    }
}

为此，您必须根据您的数据库制作BAL和DAL层。