Is there a way to validate incoming HttpPostedFile

Question

I have a couple of files I need to save in addition to some simple scalar data. Is there a way for me to validate that the files have been sent along with the rest of the form data? I'm trying to use the [Required] attribute, but it doesn't seem to be working.

Answer 1

The following worked for me.

Model:

public class MyViewModel
{
    [Required]
    public HttpPostedFileBase File { get; set; }
}

Controller:

public class HomeController : Controller
{
    public ActionResult Index()
    {
        return View(new MyViewModel());
    }

    [HttpPost]
    public ActionResult Index(MyViewModel model)
    {
        if (!ModelState.IsValid)
        {
            return View(model);
        }
        var fileName = Path.GetFileName(model.File.FileName);
        var path = Path.Combine(Server.MapPath("~/App_Data"), fileName);
        model.File.SaveAs(path);
        return RedirectToAction("Index");
    }
}

View:

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