C# 该属性属于接口类型（'；IFormFile'；）MVC核心

我正在尝试制作一个可以保存文件（图像）的表单，但它显示了一个错误：

InvalidOperationException:属性“Product.Image”属于接口类型（“IFormFile”）。如果是导航属性，请通过将该属性强制转换为映射的实体类型来手动配置该属性的关系，否则从模型中忽略该属性。 应用

我不知道如何修复它，下面是代码：

Product.cs

public class Product
    {
        public Product()
        {
            OrderDetails = new HashSet<OrderDetails>();
        }

        public int Id { get; set; }
        public string Name { get; set; }
        public string Description { get; set; }
        public int? CategoryId { get; set; }
        public decimal? Price { get; set; }
        public int? Quantity { get; set; }
        public string ImagePath { get; set; }

        public virtual ICollection<OrderDetails> OrderDetails { get; set; }
        public virtual Category Category { get; set; }
    }

创建操作

  [HttpGet]
            public IActionResult Create()
            {
                var categories = _repository.GetCategories().ToList();
                var categoriesModel = categories.Select(p => new
                {
                    p.Id,
                    p.Name
                });

                ViewBag.Categories = new SelectList(categoriesModel, "Id", "Name");

                return View();
            }

[HttpPost]
        public IActionResult Create(ProductFormViewModel product)
        {

            var file = product.Image; // **it returns NULL**
            var upload = Path.Combine(_environment.ContentRootPath, "wwwroot\\uploads", product.Name);

            if (!Directory.Exists(upload))
                Directory.CreateDirectory(upload);

            var filePath = Path.Combine(upload, file.FileName);


            if (file.Length > 0)
            {
                using (var fileStream = new FileStream(filePath, FileMode.Create))
                {
                    file.CopyTo(fileStream);
                }
            }

            var producti = new Product();
            producti.CategoryId = product.CategoryId;
            producti.Description = product.Description;
            producti.Name = product.Name;
            producti.Price = product.Price;
            producti.Quantity = product.Quantity;
            producti.ImagePath = filePath;
            _repository.AddProduct(producti);
            _repository.SaveChanges();




            return RedirectToAction("Index","Products");
        }

Create.cshtml

@model ProductFormViewModel
<br />
<br />
<div class="container">
    <div class="panel panel-default">
        <div class="panel-heading">
        </div>
        <div class="panel-body">
            <form class="form-group" asp-action="Create" asp-controller="Products" method="post">
                <input type="hidden" asp-for="Id"/>
                <div class="col-md-12">
                    <div class="form-group col-md-6">
                        <label asp-for="Name" class="control-label col-md-3"></label>
                        <input asp-for="Name" type="text" class="form-control col-md-3"/>
                    </div>
                    <div class="form-group col-md-6">
                        <label asp-for="CategoryId" class="control-label col-md-3"></label>
                        <select asp-for="CategoryId" asp-items="@ViewBag.Categories" class="form-control col-md-3">
                            <option  hidden disabled selected >Select One</option>
                        </select>
                    </div>
                    <div class="form-group col-md-6">
                        <label asp-for="Description" class="control-label col-md-3"></label>
                        <textarea asp-for="Description" class="form-control" rows="4"></textarea>

                    </div>
                    <div class="form-group col-md-6">

                        <label asp-for="Price" class="control-label col-md-3"></label>
                        <input type="text" asp-for="Price" class="form-control col-md-3"/>
                    </div>
                    <div class="form-group col-md-6">
                        <label asp-for="Quantity" class="control-label col-md-3"></label>
                        <input type="text" asp-for="Quantity" class="form-control col-md-3"/>
                    </div>
                    <div class="form-group col-md-12">
                        <label class="control-label">Select Image</label>
                        <input asp-for="Image" type="file" class="btn-file"/>
                    </div>
                    <div class="form-group col-md-12 text-center">
                        <input type="submit" class="btn btn-success" value="Save"/>
                    </div>
                </div>
            </form>
        </div>
    </div>
</div>

@model ProductFormViewModel




选择一个
选择图像

IFormFile

是ASP.NET核心框架使用的一种类型，它没有与之等效的sql server类型

对于您的域模型，将其存储为

byte[]

，当您使用视图时，可以使用

IFormFile

类型

产品型号：

public class Product
{
    public Product()
    {
        OrderDetails = new HashSet<OrderDetails>();
    }

    public int Id { get; set; }
    public string Name { get; set; }
    public string Description { get; set; }
    public int? CategoryId { get; set; }
    public decimal? Price { get; set; }
    public int? Quantity { get; set; }
    public string ImagePath { get; set; }

    public virtual ICollection<OrderDetails> OrderDetails { get; set; }
    public virtual Category Category { get; set; }
}

控制器方法：

[HttpGet]
public IActionResult Create()
{
    var categories = _repository.GetCategories().ToList();
    var categoriesModel = categories.Select(p => new
    {
        p.Id,
        p.Name
    });

    ViewBag.Categories = new SelectList(categoriesModel, "Id", "Name");

    return View();
}

[HttpPost]
public IActionResult Create(ProductViewModel model)
{
    // Save the image to desired location and retrieve the path
    // string ImagePath = ...        

    // Add to db
    _repository.Add(new Product
    {
        Id = model.Id,
        ImagePath = ImagePath,
        // and so on
    });

    return View();
}

---

还可以指定视图中的表单

enctype=“multipart/form data”

。

但我想将图片存储在服务器的文件夹中，只想将ImagePath存储在DB中。这就是为什么我使用ifformfile而不是byte[]的原因。我修改了我的答案。好的，看看第一篇文章，我更新并添加了HttpPost方法。但问题是现在将图像设为空。你知道为什么它把图像设为空吗？在你看来。在表单中指定

enctype=“多部分/表单数据”

。这将允许您同时发送文件和模型。

public class ProductViewModel
{
    public int Id { get; set; }
    public string Name { get; set; }
    public string Description { get; set; }
    public int? CategoryId { get; set; }
    public decimal? Price { get; set; }
    public int? Quantity { get; set; }
    public IFormFile Image { get; set; }
}

[HttpGet]
public IActionResult Create()
{
    var categories = _repository.GetCategories().ToList();
    var categoriesModel = categories.Select(p => new
    {
        p.Id,
        p.Name
    });

    ViewBag.Categories = new SelectList(categoriesModel, "Id", "Name");

    return View();
}

[HttpPost]
public IActionResult Create(ProductViewModel model)
{
    // Save the image to desired location and retrieve the path
    // string ImagePath = ...        

    // Add to db
    _repository.Add(new Product
    {
        Id = model.Id,
        ImagePath = ImagePath,
        // and so on
    });

    return View();
}