在我看来,第二种方式更方便。
是的,在我看来也是如此。
  在这两种情况下,如何以 html 形式上传这些图像?
相当容易。与往常一样,在 ASP.NET MVC 应用程序中,您从设计视图模型开始:
public class MyViewModel
{
    [Required]
    public HttpPostedFileBase File { get; set; }
}
那么您可以拥有一个具有 2 个操作的控制器(一个呈现视图,另一个处理文件上传):
public class HomeController: Controller
{
    public ActionResult Index()
    {
        return View(new MyViewModel());
    }
    [HttpPost]
    public ActionResult Index(MyViewModel model)
    {
        if (!ModelState.IsValid)
        {
            // the user didn't upload any file =>
            // render the same view again in order to display the error message
            return View(model);
        }
        // at this stage the model is valid => 
        // you could handle the file upload here
        // let's generate a filename to store the file on the server
        var fileName = Guid.NewGuid().ToString() + Path.GetFileName(file.FileName);
        var path = Path.Combine(Server.MapPath("~/App_Data"), fileName);
        // store the uploaded file on the file system
        file.SaveAs(path);
        // TODO: now you could store the path in your database
        // and finally return some ActionResult
        // to inform the user that the upload process was successful
        return Content("Thanks for uploading. Your file has been successfully stored on our server");
    }
}
最后,您将拥有一个相应的强类型视图,该视图将包含表单以上传文件:
@model MyViewModel
@using (Html.BeginForm(null, null, FormMethod.Post, new { enctype = "multipart/form-data" }))
{
    <div>
        @Html.LabelFor(x => x.File)
        @Html.TextBoxFor(x => x.File, new { type = "file" })
        @Html.ValidationMessageFor(x => x.File)
    </div>
    <button type="sybmit">Upload</button>
}
另外,我建议您阅读Phil Haack's blog post说明 ASP.NET MVC 中文件上传的工作原理。