public void ModifiedStatusExample()
{
using (EFCoreContext db = new EFCoreContext())
{
Department department = db.Departments.Where(f => f.Name == "Production").FirstOrDefault();
department.Name = "Production Department";
Console.WriteLine("Status Before SaveChanges " + db.Entry(department).State.ToString());
db.SaveChanges();
Console.WriteLine("Status After SaveChanges " + db.Entry(department).State.ToString());
}
Console.WriteLine("Press any key to continue ");
Console.ReadKey();
}
public void DeletedStatusExample()
{
AddDepartment();
using (EFCoreContext db = new EFCoreContext())
{
Department department = db.Departments.Where(f => f.Name == "HR").FirstOrDefault();
db.Remove(department);
Console.WriteLine("Status Before SaveChanges " + db.Entry(department).State.ToString());
db.SaveChanges();
Console.WriteLine("Status After SaveChanges " + db.Entry(department).State.ToString());
}
Console.WriteLine("Press any key to continue ");
Console.ReadKey();
}
public void DeleteMultipleRecordsDisconnected()
{
List <Department> departments = new List <Department>();
departments.Add(new Department {
DepartmentID = 1
});
departments.Add(new Department {
DepartmentID = 2
});
//Deleting Multiple Records
using (EFCoreContext db = new EFCoreContext())
{
db.Entry(departments).State = EntityState.Deleted;
try
{
db.SaveChanges();
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
Console.ReadKey();
}
private void UpdateDisconnected()
{
Department department;
//Disconnected Scenario
using (EFCoreContext db = new EFCoreContext())
{
department = db.Departments.Where(d => d.Name == "Sales").First();
}
department.Descr = "Sales Department-Disconnected Scenario";
using (EFCoreContext db = new EFCoreContext())
{
db.Entry(department).State = EntityState.Modified;
//OR
//db.Departments.Attach(department);
//db.Entry(department).State = System.Data.Entity.EntityState.Modified;
//OR
//db.Departments.Add(department);
//db.Entry(department).State = System.Data.Entity.EntityState.Modified;
db.SaveChanges();
}
Console.WriteLine("Department {0} ({1}) is Updated ", department.Name, department.DepartmentID);
Console.ReadKey();
//UPDATE [Departments] SET [Descr] = @p0, [Name] = @p1
//WHERE [DepartmentID] = @p2;
//SELECT @@ROWCOUNT;
}
public void AddStatusExample()
{
using (EFCoreContext db = new EFCoreContext())
{
Department department = new Department();
department.Name = "Production";
db.Add(department);
Console.WriteLine("Status Before SaveChanges " + db.Entry(department).State.ToString());
db.SaveChanges();
Console.WriteLine("Status After SaveChanges " + db.Entry(department).State.ToString());
}
Console.WriteLine("Press any key to continue ");
Console.ReadKey();
}
public void AttachExample()
{
Console.WriteLine("Attach Example");
Department department1 = new Department();
department1.Name = "Production";
Department department2 = new Department();
department2.DepartmentID = 10;
department2.Name = "Finance";
using (EFCoreContext db = new EFCoreContext())
{
Console.WriteLine("Status Before Attach department1 " + db.Entry(department1).State.ToString()); //Detached
Console.WriteLine("Status Before Attach department2 " + db.Entry(department2).State.ToString()); //Detached
db.Attach(department1);
db.Attach(department2);
Console.WriteLine("Status After Attach department1 " + db.Entry(department1).State.ToString()); //Added
Console.WriteLine("Status After Attach department2 " + db.Entry(department1).State.ToString()); //Unchanged
db.Entry(department1).State = EntityState.Detached;
Console.WriteLine("Status After Detach department1 " + db.Entry(department1).State.ToString()); //Added
}
Console.WriteLine("Press any key to continue ");
Console.ReadKey();
}
public void Reload()
{
Console.WriteLine("Reload Example ");
//Adding
using (EFCoreContext db = new EFCoreContext())
{
Department department = db.Departments.Where(f => f.Name == "HR").FirstOrDefault();
db.Entry(department).Reload();
}
Console.WriteLine("Press any key to continue ");
Console.ReadKey();
}
private void UpdateWrongWay(int id, string descr)
{
Department department = new Department();
department.DepartmentID = id;
department.Descr = descr;
using (EFCoreContext db = new EFCoreContext())
{
db.Entry(department).State = EntityState.Modified;
db.SaveChanges();
}
Console.WriteLine("Department {0} ({1}) is Updated ", department.Name, department.DepartmentID);
Console.ReadKey();
}
public void AddDepartment()
{
using (EFCoreContext db = new EFCoreContext())
{
Department department = new Department();
department.Name = "Secuirty";
db.Entry(department).State = EntityState.Added;
department = new Department();
department.Name = "HR";
db.Add(department);
db.SaveChanges();
Console.WriteLine("Department {0} ({1}) is added ", department.Name, department.DepartmentID);
}
}
public void DeleteDisconnectedWithoutLoading()
{
Department department;
department = new Department()
{
DepartmentID = 36
};
using (EFCoreContext db = new EFCoreContext())
{
db.Entry(department).State = EntityState.Deleted;
db.SaveChanges();
}
Console.WriteLine("Department {0} is Deleted ", department.DepartmentID);
Console.ReadKey();
}
public void DeleteDisconnected()
{
Department department;
//Disconnected Scenario
using (EFCoreContext db = new EFCoreContext())
{
department = db.Departments.Where(d => d.Name == "Sales").First();
}
using (EFCoreContext db = new EFCoreContext())
{
//This also works
//db.Departments.Attach(department);
//db.Entry(department).State = System.Data.Entity.EntityState.Deleted;
db.Entry(department).State = EntityState.Deleted;
db.SaveChanges();
}
Console.WriteLine("Department {0} ({1}) is Deleted ", department.Name, department.DepartmentID);
Console.ReadKey();
}
public void CheckStatus()
{
Console.WriteLine("Checking Status");
using (EFCoreContext db = new EFCoreContext())
{
Department department = db.Departments.Where(f => f.Name == "HR").FirstOrDefault();
db.Entry(department).State.ToString();
Console.WriteLine("Status " + db.Entry(department).State.ToString());
department = new Department();
db.Entry(department).State.ToString();
Console.WriteLine("Status " + db.Entry(department).State.ToString());
db.Add(department);
db.Entry(department).State.ToString();
Console.WriteLine("Status " + db.Entry(department).State.ToString());
}
Console.WriteLine("Press any key to continue ");
Console.ReadKey();
}