在MVC4剃刀文件上传空异常(Null Exception in File Uploading in

我创建了以下观点，与具有文件上传和提交按钮。

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

我也创建了控制器的操作方法，但它给空在一个“UploadFile”

[HttpPost)]
        public ActionResult FileUpload(HttpPostedFileBase uploadFile)
        {
            if (uploadFile.ContentLength > 0)
            {
                string filePath = Path.Combine(HttpContext.Server.MapPath("../Uploads"),
                                               Path.GetFileName(uploadFile.FileName));
                uploadFile.SaveAs(filePath);
            }
            return View();
        }

Answer 1:

ü可以尝试Name与同uploadFile

在你的页面：

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

按照@Willian杜阿尔特评论： [HttpPost]

在后面的代码：

[HttpPost]
public ActionResult FileUpload(HttpPostedFileBase uploadFile) // OR IEnumerable<HttpPostedFileBase> uploadFile
{
    //For checking purpose 
     HttpPostedFileBase File = Request.Files["uploadFile"];

    if (File != null)
    {
        //If this is True, then its Working.,
    }

    if (uploadFile.ContentLength > 0)
    {
        string filePath = Path.Combine(HttpContext.Server.MapPath("../Uploads"),
                                       Path.GetFileName(uploadFile.FileName));
        uploadFile.SaveAs(filePath);
    }
    return View();
}

见像你这样在这里同样的问题，

代码项目文章关于文件上传，

Answer 2:

尝试使用（在控制器）：

var file = System.Web.HttpContext.Current.Request.Files[0];

Answer 3:

创建模型并将其绑定到你的观点，即控制器也将预计有：

控制器：

    //Model (for instance I've created it inside controller, you can place it in model
    public class uploadFile
    {
        public HttpPostedFileBase file{ get; set; }
    }

    //Action
    public ActionResult Index(uploadFile uploadFile)
    {
        if (uploadFile.file.ContentLength > 0)
        {
            string filePath = Path.Combine(HttpContext.Server.MapPath("../Uploads"),
                                           Path.GetFileName(uploadFile.file.FileName));
            uploadFile.file.SaveAs(filePath);
        }
        return View();
    }

查看 @model sampleMVCApp.Controllers.HomeController.uploadFile

@using (Html.BeginForm("FileUpload", "Home",
                FormMethod.Post, new { enctype = "multipart/form-data" }))
{
  @Html.TextBoxFor(m => m.file, new { type = "file"});  
 <input type="submit" value="Upload File" id="btnSubmit" />
}

测试的解决方案！

HTH :)

Answer 4:

使用在控制器中的以下内容：

var file = System.Web.HttpContext.Current.Request.Files[0];

使用HttpPost代替的[AcceptVerbs（HttpVerbs.Post）]

文章来源: Null Exception in File Uploading in MVC4 Razor