Entity Framework Issue with connecting more than one table

I got products table

product table

->productID - primary

->price

->Quantity

---

productCategory -table

->prodcatID- primary

->productId - foreign key

->categoryID - foreign key

---

productlanguages - table

->productLanguages - primary

->productID - foreign key

->languageID - forein key

->Title

So I should use Entity framework and I should somehow get all products WITH THEIR TITLE,QUANTITY AND PRICE From GIVEN CATEGORY AND FROM GIVEN LANGUAGE . SO i should somehow combine info from all these three table

---

SO i started with thisuery

       var lst = db.ProuctCategories.Where(x=>x.CategoryID==catID).ToList();

and get all products from single category -> but now I HAVE NOACCESS TO PRODUCTLANGUAGE TABLE and I cannot filter by language.

If I start with

       var lst = db.ProductLanguages.Where(x=>x.LanguageID==langID).ToList();

Now I have no access to productCategories.

And I've been thinking that for hours and I can't find a way to connect productlanguages and productcategories.

---

Is there a requirement for you to have a separate Id on productCategory and productLanguages entities? If not, I would implement it this way:

public class Product
{
    [Key]
    public int Id { get; set; }
    public int Price{ get; set; }
    public int Qty{ get; set; }
    public virtual List<Category> Categories{ get; set; }
    public virtual List<Language> Languages{ get; set; }
}

public class Category 
{
    [Key]
    public int Id { get; set; }
    public string Description { get; set; }
    public virtual List<Product> Products{ get; set; }
}

public class Language
{
    [Key]
    public int Id { get; set; }
    public string Description { get; set; }
    public virtual List<Product> Products{ get; set; }
}

and then define the many-to-many relationships while overriding the OnModelCreating method

modelBuilder.Entity<Product>().HasMany(p => p.Categories).WithMany(c => c.Products).Map(m => { m.MapLeftKey("ProductId"); m.MapRightKey("CategoryId"); m.ToTable("ProductCategories"); });
modelBuilder.Entity<Product>().HasMany(p => p.Languages).WithMany(l => l.Products).Map(m => { m.MapLeftKey("ProductId"); m.MapRightKey("LanguageId"); m.ToTable("ProductLanguages"); });

This way, the virtual properties should allow you to navigate through the entities and their relations.

Please let me know if you resolve your issue.

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