asp.net - Designing classes in code first Entity Framework -

i building online shopping web application. have 4 entities :

1. customers
   • cusomerid
   • name
   • address
   • phone
2. category
   • categoryid
   • category
3. product
   • productid
   • name
   • price
   • category
4. order
   • orderid
   • customerid
   • productid
   • quantity
   • amount

please me designing classes proper relation(primary key , foreign key) maintained. tried doing database creating foreign key lead inconsistency.

my classes:

public class category     {         public int categoryid { get; set; }     public string categoryname { get; set; }     }  public class customer     {         public int customerid { get; set; }     public string name { get; set; }     public string address { get; set; }     public string  email { get; set; }     public string  password { get; set; }     }  public class order     {         public int customerid { get; set; }     public int orderid { get; set; }     public datetime purchasedate { get; set; }     public string productname { get; set; }     public list<product> products { get; set; }     public list<customer> customers { get; set; }     }  public class product     {         public int productid{ get; set; }     public string productname { get; set; }     public int price { get; set; }     public string category { get; set; }     public list<category> categories { get; set; }     } 

the problem in deciding should made primary key , foreign key , how? database adding order_orderid field in product table foreign key, itself.

your problem using list<product> products in side order. my understand property should not here. should create table orderitem contains list<product> product. can download northwind database more understand.

comeback problem. should remove list<product> products property out of class order , regenerate database.