(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

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);
    }

    ...
}

其他回答

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");        
    }
}
public ActionResult FileUpload(upload mRegister) {
    //Check server side validation using data annotation
    if (ModelState.IsValid) {
        //TO:DO
        var fileName = Path.GetFileName(mRegister.file.FileName);
        var path = Path.Combine(Server.MapPath("~/Content/Upload"), fileName);
        mRegister.file.SaveAs(path);

        ViewBag.Message = "File has been uploaded successfully";
        ModelState.Clear();
    }
    return View();
}

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">
                             

下面是我的工作示例:

[HttpPost]
    [ValidateAntiForgeryToken]
    public async Task<ActionResult> Create(Product product, HttpPostedFileBase file)
    {
        if (!ModelState.IsValid)
            return PartialView("Create", product);
        if (file != null)
        {

            var fileName = Path.GetFileName(file.FileName);
            var guid = Guid.NewGuid().ToString();
            var path = Path.Combine(Server.MapPath("~/Content/Uploads/ProductImages"), guid + fileName);
            file.SaveAs(path);
            string fl = path.Substring(path.LastIndexOf("\\"));
            string[] split = fl.Split('\\');
            string newpath = split[1];
            string imagepath = "Content/Uploads/ProductImages/" + newpath;
            using (MemoryStream ms = new MemoryStream())
            {
                file.InputStream.CopyTo(ms);
                byte[] array = ms.GetBuffer();
            }
            var nId = Guid.NewGuid().ToString();
            // Save record to database
            product.Id = nId;
            product.State = 1;
            product.ImagePath = imagepath;
            product.CreatedAt = DateTime.Now;
            db.Products.Add(product);
            await db.SaveChangesAsync();
            TempData["message"] = "ProductCreated";

            //return RedirectToAction("Index", product);
        }
        // after successfully uploading redirect the user
        return Json(new { success = true });
    }

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();
}