public void Validate_Multiple_Entities()
{
using (var context = new CodeCampContext(TestHelpers.TestDatabaseName))
{
Speaker speaker = new Speaker
{
FirstName = "Test",
Presentations = new Collection<Presentation>(new[] {new Presentation()})
};
Presentation presentation = new Presentation {Speaker = new Speaker()};
CodeCampEvent codeCamp = new CodeCampEvent
{
Topics = new Collection<EventSession>(new []{new EventSession{Presentation = presentation} })
};
context.Speakers.Add(speaker);
context.CodeCampEvents.Add(codeCamp);
TestHelpers.WriteValiationResults(context);
}
}
public void CRUD_With_Relationships()
{
// Add a new presentation through a Speaker's presentation collection.
using (var context = new CodeCampContext(TestHelpers.TestDatabaseName))
{
Presentation presentation = new Presentation
{
Title = "Another presentation about .NET"
};
Speaker speaker = context.Speakers.FirstOrDefault(s => s.LastName == "Pugh");
speaker.Presentations.Add(presentation);
context.SaveChanges();
var query = from p in context.Presentations
where p.Speaker.LastName == "Pugh"
select p;
Assert.AreEqual(2, query.Count());
}
// Add a speaker to a new presentation.
using (var context = new CodeCampContext(TestHelpers.TestDatabaseName))
{
var query = from s in context.Speakers
where s.Id == 1
select s;
Speaker speaker = query.FirstOrDefault();
Presentation presentation = new Presentation
{
Title = "More about REST",
Speaker = speaker
};
context.Presentations.Add(presentation);
context.SaveChanges();
// Requery Speaker, this time get presentations.
speaker = query.Include(s => s.Presentations).FirstOrDefault();
Assert.AreEqual(2, speaker.Presentations.Count);
Console.WriteLine("New Presentation added to existing Speaker");
foreach (var presentation1 in context.Presentations.Local)
{
Console.WriteLine("Speaker: {0}, Presentation: {1}", presentation1.Speaker.FirstName, presentation1.Title);
}
Console.WriteLine();
// Change speaker of presentation
var speaker2 = context.Speakers.Include(s => s.Presentations).FirstOrDefault(s => s.Id == 8);
presentation.Speaker = speaker2;
context.SaveChanges();
Console.WriteLine("Presenation moved to a different speaker");
foreach (var presentation1 in context.Presentations.Local.OrderBy(p=>p.Speaker.LastName))
{
Console.WriteLine("Speaker: {0}, Presentation: {1}", presentation1.Speaker.FirstName, presentation1.Title);
}
Console.WriteLine();
// Remove Presentation by setting Speaker to null in Presentation record.
presentation.Speaker = null; // This only works because Speaker is not required. If it was required an exception would be thrown on save.
// Remove Presentation by removing it from the Presentation navigation property in Speaker;
Presentation presentation2 = speaker2.Presentations.FirstOrDefault();
speaker2.Presentations.Remove(presentation2);
context.SaveChanges();
Console.WriteLine("Presenation removed. No longer assigned to any speaker.");
foreach (var presentation1 in context.Presentations.Local)
{
Console.WriteLine("Speaker: {0}, Presentation: {1}",
presentation1.Speaker != null ? presentation1.Speaker.FirstName : "No Speaker Assigned",
presentation1.Title);
}
}
}
