指定的包含路径无效。 EntityType'SpiceShop.Models.Product'未声明名为'Products'的导航属性

Question

I Have Database that contains 2 tables

TABLE Categories (CategoriesId, Name, Description)
TABLE Products (ProductId, CategoriesId, Title, ProductImageUrl)

Categories is linked to Products by CategoriesId.

I am trying to use LINQ to get all of a particular Title.

 public ActionResult Browse(string categories)
 {
     var spices = spiceDB.Products.Include("Products").Single(p => p.Title == categories);                 
     return View(spices);
 }

Product Model

namespace SpiceShop.Models
{
    public class Product
    {
        [Key]
        public int ProductId { get; set; }

        public int CategoriesId { get; set; }
        public string Title { get; set; }

        public string ProductImageUrl { get; set; }
        public List <Categorie> Name { get; set; }
    }
}

Categorie Model

namespace SpiceShop.Models
{
    public class Categorie
    {
        [Key]
        public int CategoriesId { get; set; }
        public string Name  { get; set; }

        public string Description { get; set; }
        //public List<Product> ProductId { get; set; }
        public List<Product> Products { get; set; }
    }
}

Answer 1

Just remove the .Include("Products"), that's not how it's used.

The error is clear, there is no "Products" property at your "Product" model.

Answer 2

Edit:

It looks like your View requires a Model that is a single object of type "Product".

Also, I have tried to give each of my identifiers/variables a name that best conveys their meaning and intent.

---

Edit 2:

Please note that changing any input parameter names on a method will require a corresponding change in your View code that calls the method.
In MVC, Action-Method parameters are automatically mapped .
Your debug shows a URL of Browse?categories=Sauces , which is automatically mapped to the method "Browse" with input parameter categories set to "Sauces". But (my version of) the Browse method is expecting a categoryName parameter, not categories . So you will need to make sure that URL Attribute and the Method Parameter have exactly the same name.

---

So if you really need to pass the selected Category's Name as the input parameter:

public ActionResult Browse(string categoryName)
{
    // Gets the CategoryId for the given categoryName, or zero if not found.
    var categoryId = spiceDB.Categories
        .Where(c => c.Name == categoryName)
        .Select(c => c.CategoriesId)
        .FirstOrDefault();

    // Gets the first Product (only) for the specified categoryId.
    var firstProduct = category.Products
        .FirstOrDefault(p => p.CategoriesId == categoryId);

    return View(firstProduct);
}

However, a much more common usage scenario for supporting this type of "parent-child" relationship would be:

• Your Category List invokes a query by ID when clicked, not a query by Name (ie 3, not "Pickles")
• Your View supports all the related Products, not just the first one (ie a model of type List<Product> , not just Product )

eg

public ActionResult Browse(int categoryId)
{
    var products = spiceDB.Products
        .Where(p => p.CategoriesId == categoryId) 
        .ToList();

    return View(products);
}

ie making your Product List more comprehensive, and your data access code simpler and more efficient.