(前言:这个问题是关于2011年发布的ASP.NET MVC 3.0,而不是关于2019年发布的ASP.NETCore 3.0)

我想用asp.net mvc上传文件。如何使用html输入文件控件上载文件?


当前回答

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");
}

其他回答

MemoryStream.GetBuffer() can return extra empty bytes at the end of the byte[], but you can fix that by using MemoryStream.ToArray() instead. However, I found this alternative to work perfectly for all file types:

using (var binaryReader = new BinaryReader(file.InputStream))
{
    byte[] array = binaryReader.ReadBytes(file.ContentLength);
}
Here's my full code:

Document Class:

public class Document
{
    public int? DocumentID { get; set; }
    public string FileName { get; set; }
    public byte[] Data { get; set; }
    public string ContentType { get; set; }
    public int? ContentLength { get; set; }

    public Document()
    {
        DocumentID = 0;
        FileName = "New File";
        Data = new byte[] { };
        ContentType = "";
        ContentLength = 0;
    }
}
File Download:

[HttpGet]
public ActionResult GetDocument(int? documentID)
{
    // Get document from database
    var doc = dataLayer.GetDocument(documentID);

    // Convert to ContentDisposition
    var cd = new System.Net.Mime.ContentDisposition
    {
        FileName = doc.FileName, 

        // Prompt the user for downloading; set to true if you want 
        // the browser to try to show the file 'inline' (display in-browser
        // without prompting to download file).  Set to false if you 
        // want to always prompt them to download the file.
        Inline = true, 
    };
    Response.AppendHeader("Content-Disposition", cd.ToString());

    // View document
    return File(doc.Data, doc.ContentType);
}
File Upload:

[HttpPost]
public ActionResult GetDocument(HttpPostedFileBase file)
{
    // Verify that the user selected a file
    if (file != null && file.ContentLength > 0)
    {
        // Get file info
        var fileName = Path.GetFileName(file.FileName);
        var contentLength = file.ContentLength;
        var contentType = file.ContentType;

        // Get file data
        byte[] data = new byte[] { };
        using (var binaryReader = new BinaryReader(file.InputStream))
        {
            data = binaryReader.ReadBytes(file.ContentLength);
        }

        // Save to database
        Document doc = new Document()
        {
            FileName = fileName,
            Data = data,
            ContentType = contentType,
            ContentLength = contentLength,
        };
        dataLayer.SaveDocument(doc);

        // Show success ...
        return RedirectToAction("Index");
    }
    else
    {
        // Show error ...
        return View("Foo");
    }
}
View (snippet):

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

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();
        }

在视图中:

<form action="Categories/Upload" enctype="multipart/form-data" method="post">
    <input type="file" name="Image">
    <input type="submit" value="Save">
</form>

而控制器中的以下代码:

public ActionResult Upload()
{
    foreach (string file in Request.Files)
    {
       var hpf = this.Request.Files[file];
       if (hpf.ContentLength == 0)
       {
            continue;
       }

       string savedFileName = Path.Combine(
                AppDomain.CurrentDomain.BaseDirectory, "PutYourUploadDirectoryHere");
                savedFileName = Path.Combine(savedFileName, Path.GetFileName(hpf.FileName));

        hpf.SaveAs(savedFileName);
    }

    ...
}

Html:

@using (Html.BeginForm("StoreMyCompany", "MyCompany", FormMethod.Post, new { id = "formMyCompany", enctype = "multipart/form-data" }))
{
   <div class="form-group">
      @Html.LabelFor(model => model.modelMyCompany.Logo, htmlAttributes: new { @class = "control-label col-md-3" })
      <div class="col-md-6">
        <input type="file" name="Logo" id="fileUpload" accept=".png,.jpg,.jpeg,.gif,.tif" />
      </div>
    </div>

    <br />
    <div class="form-group">
          <div class="col-md-offset-3 col-md-6">
              <input type="submit" value="Save" class="btn btn-success" />
          </div>
     </div>
}  

背后代码:

public ActionResult StoreMyCompany([Bind(Exclude = "Logo")]MyCompanyVM model)
{
    try
    {        
        byte[] imageData = null;
        if (Request.Files.Count > 0)
        {
            HttpPostedFileBase objFiles = Request.Files["Logo"];

            using (var binaryReader = new BinaryReader(objFiles.InputStream))
            {
                imageData = binaryReader.ReadBytes(objFiles.ContentLength);
            }
        }

        if (imageData != null && imageData.Length > 0)
        {
           //Your code
        }

        dbo.SaveChanges();

        return RedirectToAction("MyCompany", "Home");

    }
    catch (Exception ex)
    {
        Utility.LogError(ex);
    }

    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");
}