static void Main(string[] args)
{
Console.WriteLine($"Setup...");
using (var context = new MyDbContext(useLazyLoading: false))
{
context.Database.EnsureDeleted();
context.Database.EnsureCreated();
var parent = new Parent
{
Child = new ConcreteChild
{
GrandChildren = new List <GrandChild>
{
new GrandChild()
}
}
};
context.Parents.Add(parent);
context.SaveChanges();
}
Console.WriteLine($"Eagerly loading GrandChild entities fails (lazy loading ENABLED, no tracking)");
try
{
using (var context = new MyDbContext(useLazyLoading: true))
{
var results = context.Parents
.AsNoTracking()
.Include(x => x.Child.GrandChildren)
.ToList();
var child = results.Single().Child;
// Exception is thrown when accessing child.GrandChildren
Console.WriteLine($"GrandChildren.Count: {child.GrandChildren.Count}");
}
}
catch (Exception ex)
{
Console.WriteLine($"Exception: {ex.Message}");
}
Console.WriteLine();
Console.WriteLine("----------------------------------------------");
Console.WriteLine();
Console.WriteLine($"Eagerly loading too many GrandChild entities (lazy loading DISABLED, no tracking)");
using (var context = new MyDbContext(useLazyLoading: false))
{
var results = context.Parents
.AsNoTracking()
.Include(x => x.Child.GrandChildren)
.Select(parent => new
{
Parent = parent,
Child = parent.Child
})
.ToList();
var child = results.Single().Child;
Console.WriteLine($"GrandChildren.Count expected: 1");
Console.WriteLine($"GrandChildren.Count actual: {child.GrandChildren.Count}");
}
}
public Form1()
{
InitializeComponent();
initializeDateTimePicker();
dataGridView1.AllowUserToAddRows = false;
dataGridView1.AllowUserToDeleteRows = false;
buttonAdd.Click += buttonAdd_Click;
buttonDelete.Click += buttonDelete_Click;
buttonEdit.Click += buttonEdit_Click;
using (MyDbContext context = new MyDbContext())
{
context.Database.EnsureCreated();
}
using (MyDbContext context = new MyDbContext())
{
context.Database.EnsureCreated();
MyData data = context.Find <MyData>(1u);
if (null != data)
{
Console.WriteLine("Found");
Console.WriteLine(data.Name);
}
else
{
Console.WriteLine("Not Found");
}
BindingSource bi = new BindingSource();
bi.DataSource = context.Find <MyData>(1u);
dataGridView1.DataSource = bi;
dataGridView1.Refresh();
}
using (MyDbContext context = new MyDbContext())
{
context.Database.EnsureCreated();
MyData found = null;
foreach (var item in from data in context.Data
where data.Key == 1
select data)
{
found = item;
break;
}
if (null == found)
{
return;
}
//found.Number++;
context.SaveChanges();
}
using (MyDbContext context = new MyDbContext())
{
context.Add(new MyData()
{
Name = "이름", Number = 123
});
context.SaveChanges();
}
}
public void Create(StudentEntity student)
{
_ctx.Students.Add(student);
_ctx.SaveChanges();
}
public ProductEntity CreateProduct(ProductEntity product)
{
product = _ctx.Products.Add(product);
_ctx.SaveChanges();
return(product);
}