private static void WorkingWithDetachedEntities(QueryContext context)
{
Console.WriteLine("\nClient from non-existing context");
var loadedClient = LoadAndDetach();
Console.WriteLine($"{loadedClient.Name} - {context.Entry(loadedClient).State}"); // detached
loadedClient.Address = "Modified Address " + DateTime.Now;
context.Entry(loadedClient).State = System.Data.Entity.EntityState.Modified; // or Unchanged
Console.WriteLine($"{loadedClient.Name} - {context.Entry(loadedClient).State}"); // modified
context.SaveChanges();
Console.WriteLine($"{loadedClient.Name} - {context.Entry(loadedClient).State}"); // unchanged (but added)
}
private static void ExplicitLoading(QueryContext context)
{
Order order = context.Orders.Find(4);
context.Entry(order)
.Collection(o => o.Products)
.Load();
var collection = context.Orders.Local; // 1 order with 2 products
foreach (Product p in collection.First().Products)
{
Console.WriteLine(p.Name);
}
}
public ActionResult Edit(QueryMaster query)
{
try
{
if (ModelState.IsValid)
{
context.Entry(query).State = System.Data.Entity.EntityState.Modified;
// context.Query.Add(query);
context.SaveChanges();
}
// TODO: Add update logic here
return(RedirectToAction("Index"));
}
catch
{
return(View());
}
}
private static void AttachingDetachingObjects(QueryContext context)
{
// existing client
Console.WriteLine("\nExisting client");
Client client = context.Clients.FirstOrDefault();
Console.WriteLine($"{client.Name} - {context.Entry(client).State}"); // unchanged
context.Entry(client).State = System.Data.Entity.EntityState.Deleted;
Console.WriteLine($"{client.Name} - {context.Entry(client).State}"); // deleted
context.SaveChanges();
Console.WriteLine($"{client.Name} - {context.Entry(client).State}");; // detached
client.Name = "New Name";
context.SaveChanges();
Console.WriteLine($"{client.Name} - {context.Entry(client).State}"); // detached
// new client
Console.WriteLine("\nNew client");
Client newClient = new Client()
{
Name = "New Client"
};
Console.WriteLine($"{newClient.Name} - {context.Entry(newClient).State}"); // detached
newClient.Name = "New Client Modified Name";
Console.WriteLine($"{newClient.Name} - {context.Entry(newClient).State}"); // detached
context.Entry(newClient).State = System.Data.Entity.EntityState.Added;
Console.WriteLine($"{newClient.Name} - {context.Entry(newClient).State}"); // added
context.SaveChanges();
Console.WriteLine($"{newClient.Name} - {context.Entry(newClient).State}"); // unchanged
newClient.Name = "New Modified name";
Console.WriteLine($"{newClient.Name} - {context.Entry(newClient).State}"); // modified
}
