Exemplo n.º 1
0
        static void Main(string[] args)
        {
            var ctx = new WorldContext();

            ctx.Database.EnsureCreated();

            // Reset example
            ctx.Database.ExecuteSqlCommand("delete from Border");
            ctx.Database.ExecuteSqlCommand("delete from country");

            // Create countries
            var de = new Country();

            de.Name = "Germany";
            ctx.Countries.Add(de);
            ctx.SaveChanges();

            var nl = new Country();

            nl.Name = "Netherlands";
            ctx.Countries.Add(nl);
            nl.AddBorderToCounty(de);
            ctx.SaveChanges();

            var dk = new Country();

            dk.Name = "Denmark";
            ctx.Countries.Add(dk);
            dk.AddBorderToCounty(de);
            ctx.SaveChanges();

            var be = new Country();

            be.Name = "Belgium";
            ctx.Countries.Add(be);
            be.AddBorderToCounty(de);
            be.AddBorderToCounty(nl);
            ctx.SaveChanges();

            var fr = new Country();

            fr.Name = "France";
            ctx.Countries.Add(fr);
            fr.AddBorderToCounty(de);
            ctx.SaveChanges();

            var cz = new Country();

            cz.Name = "Czech Republic";
            ctx.Countries.Add(cz);
            cz.AddBorderToCounty(de);
            ctx.SaveChanges();

            var lu = new Country();

            lu.Name = "Luxembourg";
            ctx.Countries.Add(lu);
            lu.AddBorderToCounty(de);
            lu.AddBorderToCounty(fr);
            lu.AddBorderToCounty(be);
            ctx.SaveChanges();

            var pl = new Country();

            pl.Name = "Poland";
            ctx.Countries.Add(pl);
            pl.AddBorderToCounty(de);
            pl.AddBorderToCounty(cz);
            ctx.SaveChanges();

            var at = new Country();

            at.Name = "Austria";
            ctx.Countries.Add(at);
            at.AddBorderToCounty(de);
            at.AddBorderToCounty(cz);
            ctx.SaveChanges();

            var ch = new Country();

            ch.Name = "Switzerland";
            ctx.Countries.Add(ch);
            ch.AddBorderToCounty(de);
            ch.AddBorderToCounty(fr);
            ch.AddBorderToCounty(at);
            ctx.SaveChanges();

            Console.WriteLine("All countries with their borders");
            foreach (var country in ctx.Countries)
            {
                Console.WriteLine("--------- " + country.Name);

                // now explicitly load the neighboring countries, as Lazy Loading in EFC does not work
                //var borders1 = ctx.Countries.Where(x => x.IncomingBorders.Any(y => y.Country_Id == country.Id)).ToList();
                //var borders2 = ctx.Countries.Where(x => x.OutgoingBorders.Any(y => y.Country_Id1 == country.Id)).ToList();
                //var allborders = borders1.Union(borders2).OrderBy(x=>x.Name);;

                // better: encapsulated in the context class:
                var allborders = ctx.GetNeigbours(country.Id);

                foreach (var neighbour in allborders)
                {
                    Console.WriteLine(neighbour.Name);
                }
            }

            Console.WriteLine("=== DONE!");
            Console.ReadLine();
        }