[ Entity Framework ] Insert new record with relationship one-to-many

Question

User-590094232 posted

This is my class

public class Product
{
public int ProductId { get; set; }
public string Name { get; set; }
public virtual Category Category { get; set; }
}

How to insert this product, my problem is, I can't set category_id for this product

Answer 1

User-1219482859 posted

HI,

refer below article for your solution. its a quick and short tutorial on how to work with one-one or one to many relationships 

http://www.entityframeworktutorial.net/add-one-to-one-entities-in-entity-framework.aspx

Answer 2

User697462465 posted

Hi giangnt,

I think your class need to update, please try to refer to the following code:

The Product.cs file:

public class Product
    {
        public int ProductId { get; set; }
        public string Name { get; set; }
        public virtual List<Category> Category { get; set; }
}

The Insert method:

public void InsertData()
        {
            Product pro = new Product();
            pro.ProductId = 1;
            pro.Name = "name1";
            Category cat1 = new Category();
            Category cat2 = new Category();
            Category cat3 = new Category();
            cat1.CategoryID = "cat01";
            cat2.CategoryID = "cat02";
            cat3.CategoryID = "cat03";
            pro.Category.Add(cat1);
            pro.Category.Add(cat2);
            pro.Category.Add(cat3);
            using (DemonEntity ctx = new DemonEntity())
            {
                ctx.InsertIntoProducts(pro);
                ctx.SaveChanges();
            }
        }

Hope it can help you.

Best Regards,
Terry Guo

Answer 3

User441938976 posted

You can Initialize Object by below code :

Product p = new {
    ProductId="1", 
    Name="ProductName",
 obj = new {
     CategoryId=1,
     CategoryName="XYZ"
  }
};

If you want to more detail then you can refer below link :

http://newcome.wordpress.com/2010/06/11/c-object-literal-notation/